I spent about 9 months converting my H&K USC into a UMP. I just got there with my final polymer welding done which put the folding stock "clip" onto the gun, something that only a handful of people have done. If you really go all out, the amount of differences is so minute it is crazy. From the outside, my gun is 100% identical to a UMP, with just a few small internal changes.
I want to move on and finish my PS90->P90 conversion which I started 6 months ago. My tax stamp just got back. In the H&K world, we are fortunate enough to be able to have the full auto selector switch because we can buy the UMP lowers (which is cosmetic only since you swap out your full auto internals for your USC internals unless you want to go to jail). Is there any way to get a P90 selector switch so it shows the three settings? Anyone know the exact number of differences between the PS90 and P90 or have a link to point me to? The things I know are different: trigger group, selector switch, barrel/shroud and flash hider (which are relatively easy to change out to nearly identical).
Does the P90 trigger group work in a PS90 and vice versa?
Appreciate any/all pointers.