Its time for my 350..

i've got a 350 lined up for my van, and couldn't be more excited! but now that i've searched the site over and over, i'm wondering if it'll even fit? different head heights? and all the archived swaps pretty much include a th350 auto tranny as well, can i PLEASE keep my 3 on the tree? i like the gear ratios now, the tired old 250 will burn the right rear off at will, and the 3.36 gears keep the rpms low on the highway. how much will the power increase change the torque curve with the factory trans if i can even retain it? i have more questions than answers. and i know when i get the motor, i'm just going to yank the 6 and MAKE the V8 fit. any clarity from any direction would be plenty appreciated beforehand. my mind is melting even trying to remember all the 'van thoughts' i have everyday. i'm fairly sure my chevy has a little to do with this insomnia...

Sounds great Cope. Post lots of pic's!!!!

Go for it. I purchased my '69 Chevy with a 350/350 Turbo. Later I converted it to a 3-speed manual and now it is back to an automatic. Just a lot of wrenching. I used the same driveshaft for both trannys. The frame has four threaded factory holes up front to mount your clutch pedal assy. Take your time and it will all work out.