Replacing ALL 4 speakers due to factory speakers going out.

I have read quite a few threads here but still need some advice.

1) What size are the front and back for our crew cab truck - 6 3/4" ??
2) Will 6 1/2" speakers work? Seen threads were some guys have done this.
3) Does my truck (01) only have speakers in the doors and no tweeter?
4) I have never taken the door panels off - I need instructions ??
Past exp. I have normally tore something up doing this and need
all the advice I can get !!! Ha !

I am pretty sure ours is not a Bose system (factory). I also what to keep my replacement speakers something like Pioneer because we are older and
some times crank it up but nothing major. Just want to replace the speakers with a modest budget.

Thanks ahead for your advice !!!

Hey Redbrand, doesn't look like you've gotten any responses so I'll answer what I can. I may be corrected by somebody as I'm new to my 02 DMAX but am in the process of replacing all stereo components in mine so have learned some things over the last couple of weeks.

1) The speaker sizes are 6 3/4"
2) 6 1/2" are what you'll put in, they're the closest to factory you can buy.
3) There are no tweeters
4) Can't answer that at the moment but will let you know when I get it figured out.

You can tell if you have a Bose system because your front speakers will have Bose written on them.

I replaced my front speakers, and there is a little tweater above the speaker. And I may be standed corrected on this, I think it's the LT that has tweaters on the pillar between the windshield and windows. It might be the LS, I always get the two confused. Anyways if you do have them you'll know, because it's stickin right out easily seen. Mine does not have them, the only reason I know this is because when I ordered my pillar gauges, they needed to know if I had the tweater because the case that holds the gauges would have a hole for the tweater.