Do you still have the circuit breaker in place, or did you swap in the new fusible links? Honestly, I'd continue to run the breaker until you know the issue has been sorted out. Maybe try doing a few torque-stands to simulate the steep uphill climbs.
I had it out for a while while I was debugging, as suggested by Linus and I waiver about if it might be an issue, but I don't think so. As of now I had the same idea as you and it's in, acting as a crappy version of the fusible link. I will return it back to stock eventually. The fusible would take > 30a for a short time without burning out. The breaker would blow and reset in a few seconds right at 30a. Kinda the same and I see why someone might do it this way, but I prefer it to be stock and original.
Torque stands were able to simulate the steep uphills and the stuttering before. I forgot about that. I'll try it. I still haven't taken it out for a drive. We took my 911 over to get aligned on Mon and picked it up today. My is way afraid of the 80 dying on us now.