Holy Trainer Fitting and Comfort Questions

I recently got fitted at a shop for a new Holy Trainer. I went with the ring size of 50 and opted for the shorter shaft piece. Before this, I wore CB6000 models; after wearing them for extended times, I noticed the thick ring was quite painful on the bottom of my scrotum. The Holy Trainer’s ring feels much more comfortable overall, but there is some discomfort once I slide the shaft into place. Unlike the CB devices, the Holy Trainer doesn’t have spacers built in. This makes me wonder what others do when they find it a bit snug around the testicles while locked up. Any tips would be great because I’d like to wear it for several days at a stretch.