I don`t recommend you get a carb from Carbs Unlimited, who specializes in Q-jets, I already did buisness with them. when I got it, it looked new, had new throttle shaft bushings installed, so I had bright hopes for it, I installed it, it ran great, I was happy, until I shut it off. the well plugs, which had been sealed with epoxy, leaked down faster than I ever seen any leak down, even while running I noticed they leaked down, I took the carb back off, took off the base plate, stripped the epoxy off, restaked the well plugs, added new sealant, let it cure under a heat lamp for 36 hours, reassembled, installed it, same problem, I called carbs unlimited and they told me it wasn`t possible that they leaked as the carb was tested before it left on a dyno. since I had resealed them, they refused to warrenty it. however there are other places to get Q-jets, Jet, makes performance Q-jets, they have stage 1, 2 and 3, they cost a bit more, but worth it. they have the basic replacement up to full race Q-jets. Edelbrock also makes Q-jets. Q-jets are great carbs, and there simple to rebuild, here`s a site I learned alot about them and these simple mods prove to be effective.
there`s other things to lean of Q-jets, like the hanger numbers, metering rod codes and etc, Doug Roe has a book on Q-jets which is real helpful on building them as well as performace mods. good luck silver.