I bought a big, well-used pipe wrench at a pawn shop and dulled the teeth with an angle grinder. It holds just fine on the almost-square shape of a driveshaft yoke, but it sucks at grabbing onto a pipe or other round stuff now. I've got a huge chain wrench for round stock.
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!