That price is about right. Go with the FMS gears, especially if you install them yourself. Ford controls the tolerance on their gear sets very closely. Allowing for easier installation. You can probably use the existing pinion shim and install a set of FMS gears and the pinion depth will be right on (of course you must check it)
A gear install is not rocket science. Certainly not for a beginner but with a good understanding of the procedure you can do it in your garage with a few special tools. You will need a pinion depth gauge, gear marking compound, impact wrench is nice but not required, in/lb and ft/lb torque wrench. There are several good articles out there that help, video tapes, and check out the article at the corral. Written pretty well with pictures.
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fordgasm
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