Is this an M22 rock crusher, or is it a "compound low" 4-speed? I think either way, if the rearend has the original gearing, you'll either have a 4.10, or something in the "mid-4's" gearing. If I'm not mistaken, your trans may be "floating", with the bell-housing mounted to the crossmember...is that correct? If so, you may have to find or make a trans. crossmember. Also, if you have a compound-low trans, you'll have to shorten the driveshaft, and get the correct yoke for the Turbo trans. Running a trans cooler and lines is simple, and installing an aftermarket shifter is a piece of cake. But of course, with an automatic, there will always be some slippage, so your engine will run a little faster...even faster if you use a higher "stall" converter. And also you'll need a "400" flexplate, which is sold at most performance shops. Why are you switching to automatic? Just curious
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