I have been having a play round with a few mods on some of my airfix mkII's and found a chisel craft blade enough to move chop,chisel & slice out most of the fiitings with ease.
I dont know why I thought they be harder to remove than they it actually turned out to be.
I have done two buffer beams also, by cutting square across inner square section, which then just needs a fillet of strip and a new buffer beam from Souther pride and jobs a good un!
Ian