“Free” is rarely actually free. If it is actually free, I’m assuming that it’s a rebuildable core, not a solid running engine. Also not so many 3rd gen camaros came with 350’s, and I may be wrong but I don’t think a tbi 350 was offered at all in those cars. I believe in ‘86 or’87 they came out with the Tuned port (TPI) 350 as the only 350 option for these cars, and 305’s were available in carbed, tbi, and tpi variations. Millions were built with 305’s though too so before you go through the hassle of pulling it, check the block number and verify it is a 350.
If it is a 350, and it is free, go get it. You can always use it to offset a core charge on a reman/crate 350.
My advice, putting a tbi 350 in there will be the most cost effective engine upgrade. Bolts right up, wiring harness needs only minor modifications if any to work. A v8 distributor and tbi unit and you will be off to the races.