We have 3 third gens in our region running carbed 350s. They all make good numbers and are stupid simple. The 350 with a LT1 T56 makes a pretty solid setup. Bryan White has been running this setup for several years and it has been very reliable. The downside is that some are actually on the high side of torque so you have to be careful of your exhaust configuration so as not to build too much torque. The other downside they are iron head iron block. Still waiting for someone to submit a RCR to allow the 80s corvette aluminum heads.
Bob