You might try contacting this member on ls1tech
http://ls1tech.com/forums/member.php?u=19317 I tried searching for some ZL1 info and didn't find any good info from a quick search but he seemed to have a lot of info and owns 3 GMMG cars. It actually might be worth it for you to sell the motor and buy something else and make some profit off of it, but I dunno what it'd sell for.
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1972 C10 LWB Highlander Dark Olive/White - Work in progress 5.3/6L80e, Accuair e-level, Porterbuilt Stage 1 front and Stage 2 rear, Wilwood 14"F 13"R, Vintage Wheel Works V40 18x8/18x11, and more...
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