loner, here are 109 dyno-tested SBC combinations. Look through here and see what suits your fancy, then price the parts to do the build and add machine work.
http://www.ryanscarpage.50megs.com/combos1.html

As far as the trans, 2,800 lbs is considered the weight limit in drag racing before you should swap out the 'glide for a TH350 or TH400.