I think you can build up the 350 safely to get decent power and keep the TBI. I would imagine you will be looking at bigger injectors and a remap of the computer, neither of which are a big deal. I would also suggest headers of some type, CARB legal, of course.
The 700 and 208 should be fine; you may want to go through the trans if you are going through everything else (it is 20 years old, too).
The only thing that I would change in your scenerio is the gear you are going to use. With 35's, you might want to lean toward 4.56's, just to get them moving. Put trusses on the 10 bolts, and they should be fine at teh power level you are wanting to achieve.
Also, before everyone else says it,