Ok to many types I can not keep the all correct.
Compact 14 rnd
75b/85 15 rnd
Sp01 19 rnd
What fits who?
All the bigger fit in smaller, but, P01 use Compact mags? 75b is longer, what is the stock mag 15 rnd or 16?
The Compact model, P01 and P06 all use the compact mags.
Allright cool that part helps.
Regarding the pre-B, mine came with a current 16-rounder. As for the filing, it's all on the back face of the magwell in the frame and it's highly advised to pull out the safety and sear pack to do the work, there will be *lots* of metal filings in there.