Thanks for doing a video on this👍😀 To be able to keep the bore clean during fabrication, I usually just ball up some aluminium foil and stuff it in there.

Dang dude, that looked really difficult. You should invest in a vise. Quit fighting all those scrap metal pieces and just use a 3/8” X 6”bolt with some washers and a nut to pull the assembly in using the large socket for clearance. That works pretty easy.