Fleetwood model 4068... Advice?

[VintagePC]

Good news- I've sourced a variac that I can borrow.

With this, I've read that the procedure is to bring the set up in steps (typically 10v steps/30 min?) Can someone confirm or provide a link to a good guide for doing this? I've found a few, but those all discuss re-forming the original filter caps and precautions if you're bringing the set up with the original paper caps- I'll have replaced all of those by then, so I don't know if the process differs much.

There's also something about a point around 40-50V where things get near the minimum operating voltage to run, and that it should be left there for longer.

Thanks!