If you can find a parts store with the old school paper catalogs instead of a computer, (and an old geezer counter man who knows how to use it) Spicer and a few other driveline component makers have dimensional charts that allow you to use measurements from the old U joints to select the right application. There are even "adapter" U joints with different diameter and spacing of the cups for the shaft and yoke for special applications.
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!