All years are the same, just look out for the L99s. Corvette LT1s (and factory replacement LT1s) are 4-bolt main. 
Need block.
Cooling system. On gen 1 motors the coolant goes into the block around all the cylinders and trickles up to the heads. IN an LT1 the coolant goes into the block but immediately makes a 90degree turn up into the heads and then around the chambers and back down around the cylinders and forward.
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A few checks you can do is to; look at the front waterpump holes, if there is 4 on the sides of the timing cover and the top holes go up into the deck then you might have one. There is also a 327 stamped on the side of the block and they will never come with a mechanical fuel pump boss. It will save you a lot of time when looking at craigslist or junk yard "lt1s."
I live in Raleigh and am working on a car in Durham. Why do you need a block? Looking to get a rebuild on the quick or doing a 'steady as she goes' project?
I have a short block you could have for free. Problem is it's seized due to previous owner's negligence (overheated, blew head gaskets, hydrolocked). I haven't torn into it so I don't know if the rods are bent or anything else is trash (crank, block, main caps). I'm pulling it out this weekend, probably. Been prepping the replacement I bought.
So... it's yours if you want it; you can disassemble it and have it magnafluxed for cracks, deck it, bore it, and go for a nice 355 build. Or sell it for scrap if it's NFG. PM me if you want to talk about it.
I have a short block you could have for free. Problem is it's seized due to previous owner's negligence (overheated, blew head gaskets, hydrolocked). I haven't torn into it so I don't know if the rods are bent or anything else is trash (crank, block, main caps). I'm pulling it out this weekend, probably. Been prepping the replacement I bought.
So... it's yours if you want it; you can disassemble it and have it magnafluxed for cracks, deck it, bore it, and go for a nice 355 build. Or sell it for scrap if it's NFG. PM me if you want to talk about it.