XJ750 Maxim overcharging

I have a 1982 Xj750 Maxim and I am having problems with the electrical system. I just recently bought this bike and realized it was charging to 15.5 volts at anything over 2000rpm. I checked the rectifier per the manual and ended up buying another one OEM and same exact results. I have cleaned the flywheel rotor and made sure slip rings and stator connections had good resistance. What i find weird is when I pull the fuse for the headlight the voltage still goes up but it takes a while before it hits 15. I can't seem to find a short anywhere I have also tried a different battery. Would love any ideas on what this may be. Thank you

 

If you search, there are LOTS of threads here about similar symptoms. There's a really good write-up somewhere of how/why dirty contacts results in over-charging, but I can't google-fu it up right now. Might be in here, near the Charging System Overview: https://www.xjbikes.com/forums/threads/the-ultimate-relay-switch-sensor-and-diodes-guide.27543/