You mentioned this 3 or 4 times and are exactly right. Measure stock shock(or known working shock) fully compressed and fully extended center of mounting stud to center of mounting stud & mounting stud dimension. Exactly what I did for my '38 Ply Coupe. Took those dimensions to Napa and looked through their book myself, less than 10 minutes, had the part #'s I needed. Each page has the different mounting type designation & with that and the dimensions, found something within a 1/2" each way. My car is lowered, so I adjusted the measurements accordingly. On vaca, so no access to my car for part #'s, but I think all 4 were the same (again, lowered, so stock is out the window). Good luck.