I recently bought a replacement bumper and I'm looking to get 305/70/16's to fit on 16x8 Rims. Everything I see about the T-bars and the ride doesnt appeal to me, but I'll do what I have to.

Do you think I'll still need to raise the front end, or is that just for factory fronts?

My 33's (same as 305) took some tb lifting to fit. My ride is better than stock except for speed bumps.

With the added weight of the bumper you will most likely want to level it out. You can either go with the torsion bar keys, green keys, or you can look into a leveling kit from a lift company. You will find tons of info on here about that. Good luck.

who makes that bumper?

Thats a Ranchhand Bullnose. Funny part is that before I bought mine last week I searched the internet high and low and could never find a picture. Now I have posted pics of mine, and here is someone else with one. They are nice bumpers. Pictures of mine are here:

http://dieselplace.com/forum/showthread.php?t=65176