I think* that the two inch blocks will make it sit higher in the front, so if anything, maybe some one inch blocks. I would put the springs in, drive around for a while (month or so) to let the springs settle, then decide. Putting the blocks in is relatively easy.
As far as the motor being too much for the truck, do you mean as far as getting traction, or just frame twisting power? Cause I kinda doubt either will be an issue, not with that gearing, and not with these frames.
Hope that helps, I'm no expert, so maybe someone else can confirm or deny my assumptions.
