pain in the rear...
like said above drop the K, get 3 jacks....1 for the motor, one for the tranny(safety measure) and one for the crossover on the midpipe(IMO)...plan on a weekend job.
As far as power on a N/A 4v....I gained 14hp off the start....with a tune I made 294 with LT's, o/r mid, mac 2.5 cat back and a JLT CAI....301 with steeda pullies.