"Interestingly my interchange catalog lists the upper A arms being the same from 52 through 57.  Moog also shows them using the same bushings."

There are large differences in FORD SERVICE PARTS and aftermarket. Aftermarket tends to allow more 'probably will fit' scenarios than FORD. And again there are large differences in FORD ASSEMBLY and SERVICE PARTS. FORD also will replace original service parts with later service parts or specialty parts to remedy certain situations.

MOOG (and TRW) are not what they once were. MOOG used to be a first class act.

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