Anyone know anything about these?

I picked up a NOS parts kit a couple days ago because why not lol, it seemed like it might be a fun project. Got everything unwrapped today and three things instantly have me scratching my head. I already know all the basics on it but...

The first and probably most important being that the barrel is not centered in the tube. I'm assuming it should be just from prior experiences with tube guns, but on mine it is noticeably pointing down hill. Digging around online and I can't find anything anywhere that can tell me if the barrel and block can even be removed to start with, much less how someone would go about doing it.

The second and and more easily rectified is on the safety selector. It looks like it should be held in with eather a clip or a spring, neather of which I have, but that is easy enough to just grab a E clip from the hardware store if that is actually whats needed.

The third is, on the trigger pack there is a small plastic block on the trigger pin. Mine looks like it is actually broke but not enough to where it will come out. What does that actually do and how necessary is it actually? Clamping the trigger pack on the tube and cycling things, everything seems to be working properly so I'm kinda leaning twords not worrying too much abut it for now, but If I can find a replacement or possibly get it out without it breaking more, I could probably just draw up a replacement ad 3D print it.

This message has been edited. Last edited by: PakRatJR,

Same junk as the Intratec TEC-9, Claridge Hi-Tec and Feather Industries AT-9.