".1m600 715p"

I had a box full of Caps, a number of which I hadn't labeled as to value, so I spent a couple of hours doing searches on the internet on various combinations of the cap markings:

715p seems to relate to Orange drop style Polypropylene film capacitor.

The 600 appears t be the volt rating.

The .1m relates to the value--the m tells you how many decimals to move. This is where I get weak on my recollection. I think mine were labeled K instead of m (I'm not at home, so I can't check just now), which I recall meant moving the decimal 3 places (.1k would become .0001). However, it could also mean .1 microfarad :\ . I don't recall how many decimals one deals with for micro farad vs pico farads and the various symbols that represent them (e.g., that u looking character that might me called "mu"?).

Since mine were all bought for BL single coil and humbucker pickups, it helped that I know the range of possible values (most micofarads, while the treble bipass was picofarad; I still had the receipts for many of them with the values listed, so it was kind of a matching game).

Here is something I found on a website that might help with the relationships of mF to pF:
".0022 mF (2.2K pF)"

Another quote-
"I have seen some (not all) old schematics that assumed mmf (same as pf, 10 to the power of -12 farad) unless otherwise noted for all capacitor values. That way they avoided using a decimal point for whatever reason. So your 10K, if that means 10,000 mmf would be 0.01 mf. And mf means microfarad (10 to the power of -6 farad) every time I have seen it, whether capitalized or not. See if these guidelines give you sensible values given the context of the circuit. "

Hope this helps with your value determination effort.