I have a good many amaryllis outside in the ground zone 8b. Some have bloom stalks up right now while many don't. I really need to move most of them due to the fence having been removed & they are now right out in the pathway. It will be pretty hot here soon so when would be a good time to transplant?

I ones transplanted my amaryllis in the middle of a local summer,. when outside was about 95-98 F (in the shade) and dry too. As long as you transplant with leaves and roots, and ground remains wet all the time, they survive (at least a local strain that we have here, no idea about the strain that you have in US)

The only ones I would hesitate to move right now are the ones with buds on them - I fear the bud could die. But even if it did, I think the actual bulb will survive. In addition, I think moving any of them while actively growing might cause them to skip a year a of blooming. Other than that, I think they will all survive if you move them now. Waiting until Fall is better, but if you can't do that, I would just move them and try to take good care of them while they make that transition.