Spacer for what? if you try to raise the dist. out of the block, you will not mesh the gears properly and it may jump out of the oil pump.
Are you using the stock '63 sidecovers? try looking at a '75 or newer engine. Maybe they added a larger depression in the sidecover for extra clearance? I noticed that the aftermarket ones that Langdon sells have clearance cutouts. Try looking at the local salvage yard or maybe call Langdon, or try the local Chevy dealer, since these engines are still available new. There is nothing that I could find in Leo's book about any interference issues. Perhaps turning it so that the cap clamp is in the middle of the sidecover depression would work better?
