Hmmm. . . if this is going to be a true player for you, you might want to just pull the entire harness and build a new one using new quality parts and specific to your liking. It's always dicey when you have electronics that are close to 60 years old, and you have no idea what they've endured. I did this with my '59 T-100D. If I need to restore it to original, I can always do that, but I'm more concerned with it being a solid player vs original vintage.
Guild commonly used a 200k tone pot on the neck PU with a 0.047uF cap to tame the high-end bite of the mini-humbuckers. The rest of the pots are usually 500k, with a 0.022uF cap on the bridge PU. For the schematic of an original mid-60s SF with minis, check GAD's site here:
https://www.gad.net/Blog/2019/03/13/1966-guild-starfire-iii/
The 200k tone pot is commonly swapped out for a 500k, and the 0.047uF cap lowered to a .022uF, or sometimes even a 0.1uF or 0.15uF cap. Guild did this with the updated Newark Street Guild Starfire IIIs from the mid-2010s, and Fender did this with the late 90s-early 2000s reissue Starfires. (Schematics also posted on GADs site.)
If you also do a search on this site, you'll find others who have encountered this issue with multiple suggestions and solutions.
Hope this helps!