I did try that exact method, but it felt like there was quite a bit of resistance so stopped for fear of damaging the fill port. I'll give it another...
A question for anyone that has stripped an Axsor/FX2000/ Excalibre... is there a way to remove the filler end without completely stripping the whole...
I reckon if you can knock out machine, cast or 3d print receivers which now you can do in a metal material to the correct identical spec pattern etc...