Here is a suggestion..... look in the phone book for a local alternator/starter re builder. Sometimes these shops carry battery cables pre-made in different lengths and in different sizes. Also, sometimes, these shops make custom cables also (usually using welding cable, which is finer and a bit more pliable).

Also, there is an E bay seller that pre-makes cables for the 6.5L.
Here: http://www.ebay.com/itm/CHEVROLET-GMC-6-5-TURBO-DIESEL-2-0-BATTERY-CABLES-/320815622091

I don't know the length, but you can contact and ask. If they are long enough for a top post.

Also, have you tried the nut and bolt trick vs the OEM style battery bolt? It is using a 3/8" bolt and nut to secure the cable to the battery. You put the bolt (forgot lengh, thinking 1") w/ the nut on first, then run the bolt through the cable eye, tightening the bolt into the battery threads, snug & bottomed out. NOT too tight. Next you tighten the NUT against the battery cable (using a lock nut might be better). Posts on it here say that it holds much better....

 

A forum member makes a nice looking cable set.

http://ptwiringsolutions.com/Home.php

I made mine and probably overpaid for materials before finding these. They look nice!

 

Those cables on Ebay and from PT Wiring solutions are exactly what I want, except designed for the top post battery terminals. I have already bought and installed new top post batteries. I'll call and find out the lengths and have new ones made up at a local shop or at this place I found.

http://custombatterycables.com/index.htm

Thanks for the replies!

 

Are you in Dallas?

I got it from a place in Dallas called Alterstart. You can google it.
I told them what I want and they make it for me with 2 gauge cable with properly tinned, crimp and heat shrink at the end..
It has been there for around 5 years.

IIRC, using the side post cable, length is around 87" for positive to positive. May be add a little bit more for top post say 8 ft.
I also combine the cable to alternator with one of the terminal to add another 36" or 3' branch to alternator.
Mine is a 95 so the alternator is on the driver side. Not sure on the pass side alternator.

Not cheap but it is worth it.

 

You could always just PM Racedaymechanic and ask him if he does custom work.

He obviously knows what he is doing and could probably hook you up with some top post mount cables.

 

I realize this post is now 10 years old haha but I just did a battery cable upgrade and thought I would share the lengths that worked on my 93 GMC k2500 automatic

I was looking for this answer so I could get some shipped to me without needing to strip off the old ones to get measurements, I ended up taping a sting along the old ones and measuring that which was close enough, I just guessed on the one for the starter

I'm in Canada and used this site, Battery Cables Canada
they ship em for $5 nation wide which is very reasonable, the cables look like good quality
after I ordered them I realized the local chieftain auto parts had pre made ones on the shelf the whole time haha.

Also for any newbies out there like me 2/0 is considerably larger than 2ga. my understanding is you could build your cables out of 2/0 or 2ga and both would work, you should get less drop in voltage with 2/0, the price difference didn't seem huge so I went with 2/0. I believe the stock cables were made with 4ga

drivers side
-red battery crossover + to + 72"
-black driver battery ground to engine 24"

passenger side
-black battery ground to engine, ( I did mine 24" and it worked but it was tight, 28" or 30" would be better)
-black battery ground to frame 6" long ( I did mine 6ga)
-red power to starter 48"
-red power to power post block on passenger side firewall ( i think this is just for 1993 years and younger, i did this in 4ga, routed wire behind air intake. The stock cord for this is routed with the stock starter cord then comes up the firewall, I just cut and capped this cord and ran the new 4ga)

I haven't gotten around to it but I'm gonna run a new wire from alternator to my battery 36" should be good.
I got the top post adapters at chieftain auto parts.

 

I realize this post is now 10 years old haha but I just did a battery cable upgrade and thought I would share the lengths that worked on my 93 GMC k2500 automatic

I was looking for this answer so I could get some shipped to me without needing to strip off the old ones to get measurements, I ended up taping a sting along the old ones and measuring that which was close enough, I just guessed on the one for the starter

I'm in Canada and used this site, Battery Cables Canada
they ship em for $5 nation wide which is very reasonable, the cables look like good quality
after I ordered them I realized the local chieftain auto parts had pre made ones on the shelf the whole time haha.

Also for any newbies out there like me 2/0 is considerably larger than 2ga. my understanding is you could build your cables out of 2/0 or 2ga and both would work, you should get less drop in voltage with 2/0, the price difference didn't seem huge so I went with 2/0. I believe the stock cables were made with 4ga

drivers side
-red battery crossover + to + 72"
-black driver battery ground to engine 24"

passenger side
-black battery ground to engine, ( I did mine 24" and it worked but it was tight, 28" or 30" would be better)
-black battery ground to frame 6" long ( I did mine 6ga)
-red power to starter 48"
-red power to power post block on passenger side firewall ( i think this is just for 1993 years and younger, i did this in 4ga, routed wire behind air intake. The stock cord for this is routed with the stock starter cord then comes up the firewall, I just cut and capped this cord and ran the new 4ga)

I haven't gotten around to it but I'm gonna run a new wire from alternator to my battery 36" should be good.
I got the top post adapters at chieftain auto parts. View attachment 657015 View attachment 657016

Looks good👍I bought the same top terminals at Napa.

 

(5) DIY: - Making New Battery Cables for a 93- 6.5 | Diesel Place