It sure is a mess and difficult to sort out what's what! I can't imagine all the variations in driveshafts Between Engin/Trans and rear axels 8" 9", Gear ratio, and 28 & 31 Spline. No wonder Ford build Sheets needed 4 color code bands to get 24 combinations to cover all the drivetrain combinations available on a Mustang/Cougar. That's why Ford used color codes when picking some parts on the assembly line, it was less error-prone than reading part numbers. Anyway, I probably read it in your posts, but please confirm your car is a....
Year: 1971 Mustang
Trans: factory C4, C6 or FMX, or a manual 3 or 4-speed Toploader: Yes
Factory ride height: Yes
and you are looking to maintain factory engine height and driveline angle and ...Correct?
71-72 Convetible/429ci Frame mounts paired with 71-72 Motor Mounts. I have the frame mounts and the motor mounts, but you can easily get the motor mounts from your local parts store or online. It's your call on those. Message me if you are interested in them.
The total height from where the frame mount (perch) bolts to the cross-member and to the very top of the complete assembly should be 6 1/8". If it comes up short, it will not meet your block's mount holes correctly and the engine will not be at the right height.
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