It was a (IIRC) approximately a 1/2 reamer (drill bit) 12 inches long.
The tubes outside diameter was was just under to be able to slide in. You cut the tube length to one half of the blocks inner galley. Drill/ream from front and back side of the block, fit the tube half way and make sure they meet in the middle.
The peen tool was a solid .904 diameter bullet shaped slug of steel to be driven past the tube.
The tool to drill the hole in the peened tube looks like anlifter with a slice taken out of it and a hole for the drill bit to guide it to the tube and hold it steady so you can drill the hole in the tube.
All parts are pretty much made of unobtainum these days. Except the tube and drill bit which can be obtained at any decently stocked hardware store.
YL gave good instructions on that.
An old lifter ground down can be the peen tool. Drilling into the peened tube can be a trick. But shouldn’t be overly difficult.
