I did it, I seem to remember you have to drill out the fastners for the original cap, but the chevy cap and rotor fit right on it. Just give MSD a call they can give you the correct part numbers for this swap, the guy at the parts store I was dealing with turned me on to this mod saying alot of Mustang guys did it. I still have the original cap in the garage. I sold so much 351 stuff before we got 1717, and now I wish I still had it all.Here is the number and address of the place that turned me on to the smaller cap.
Ramchargers Performance Connection
4764 Dixie Highway, Waterford, MI 48329
phone (248)-673-3400
Jeff
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