Does anyone have a lead on a supercharger for a 2004 3.4 liter motor. I found a lot for the 3.8. Are the blocks the same?

Far from it. I dont think the 2 share a single piece. The 3400 is a 60 degree V6 that started life as the 2.8 liter option in the 1980 X-bodies. The 3800 V6 traces its roots to the early 60's. It has a balance shaft to make it smoother. The 3400 doesnt need that because it is a 60 degree V6.