Bren MKII to L4 Gas Shield

[Brit plumber]

b) the corresponding projection in the gas blast plate is twisted .

This is what both myself and Kev have said, its the locating bits on the gas shield which have distorted, when you zoom in on the pic you can see it twisted.

---------- Post added at 12:17 AM ---------- Previous post was at 12:15 AM ----------

Well I am going to try and disassemble the gas cylinder as I have nothing to loose. If the front section is twisted I will need to locate a donor portion. As far as the pin goes, do you have any tricks for getting the pin out? I shattered two pin punches in the press, shattered two drill bits, completely bent a nail set that I modifies in the lathe. Its not going well. Started to drill out, still no luck. Now I have a hole all the way through on center and the thing still wont budge. I am running out of options!

Not teaching you to suck eggs but did you press the pin the right way?