straps and u-bolts don't sit on the same part of the u-joint cap. If you drill a strap yoke out and put a u-bolt on it, it will sit inboard just a hair on the cap, putting pressure on the bearings instead of the solid face of the cap, and cause premature failure.
I got a nice lecture on it from the local driveline shop while I was buying a u-joint and a new yoke..
You can find u-bolt 8.25 yokes from most aftermarket driveline shops - try Tom Wood or JE Reel.