Tommy, they are M8 Star. Last time I was over there the Sears Craftsman store had the right wrench.
If the bolts are mangled here is a trick. Early Amphicars used the same bolt to hold the rear brake backplate on but they aren't needed there, ordinary hex head are fine, so take to ones from the backplate for the props (where you can't use hex head as they touch the UJ yokes).
Sorry, no idea about the UJ, although I know someone in the past mention an alternative that works.
David C
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