[davepl]

I am not a guru and I cannot solve this problem but will raise one just to make sure you're aware of the issue.

Between "classic" big and small blocks and the LS motor there is a difference in how far back the face of the flywheel is vs the old motors. It is .450 less further back, I think.

So, to run my LS3 with my old Hayes clutch and TKO-600 trans that come straight off the 502 big block, "all" I had to do was buy a special GM flywheel that is .450 thicker than normal. That is GM part number 12561680 and runs over $400 and there apparently cheaper ways do it with a truck flywheel, etc, but I don't know the details.

So, when I saw "LS to Old Trans" I figured I'd better post this little nugget! What I wouldn't have paid for the knowledge in the previous paragraph, would have saved me some time!