Tracy, did you lower or raise (by.75"?) the thrust line on your RV4?  I thought that you lowered your engine so the alternator would not require such a large blister but now as the years have passed I'm not so sure.  I built my motor mount to put the thrust line at the stock location but I am considering raising it so I can run a longer prop.  Note that I bought the engine mount in 2002 so I have the longer gear legs.  If you lowered your engine I probably will not bother to make any changes but if you raised the engine I will probably need the extra prop clearance.

Ken Powell