Honestly, if I could do it all over again I would just go with a 350 w/tbi, the vortecs are nice once you get them dialed in but plan on spending more and dealing with certain bugs that come up along the way. I won't go into depth but all in all the tbi will end up being an easier swap. I will say once you do get the vortecs in they are fun to drive though........just depends on how much hassle you want to deal with. Things like : wiring harness, O2 sensors, reprogramming computers, etc. end up adding cost and time to the conversion.
Noah