One of the bearing caps on the u-joint spider is loose when bolted into the front differential. I can spin it with my fingers and both bolts were loosened and re-tightened. Still loose. Other side is tight.

Is this a bad yoke or a bad u-joint?

The drive shafts are painted black with Accurate written on them. Spicer grease able u joints installed from last owner I guess.

Try to flip it 180 degree's and see if it does the same thing. If it does, it's the yoke, if not, then the u-joint.
If you have a micrometer you can measure the u-joint.

Replace the straps that the bolts go thru they stretch.