I'm am replacing exhaust manifolds,riser elbows and intermediate elbow. I'm am having a problem finding the right intermediate elbow. My engine is a '96 5.7 Mercruiser W/alpha one gen 2. There is a 3" spacer on the manifold, the only casting numbers on the exhaust tube are MH 64560. I can't seem to find any with this number. Does anyone have any cross references for different ones that will fit. Nothing I can find shows any for that engine with the 3" spacer. Any suggestions would be greatly appreciated, Thanks