Ever since I found these rotary nylon brushes this cleanup was an annoying job. It does help to soften the brushes with acetone or some other solvent as they cut very hard when new...
Getting the crank in and out appears to be a huge issue for some people, but the tool required is actually just this mounting bridge with some M8 threaded bar cut to length. The nuts on the end of the rods are just to make it easier to hit the bearing face and not the rollers.
Re-installation of the crank in (pre-heated) cases is a dead simple affair where you snug up the nuts left and right and then just pull the crank in.
Installing an old gudgeon pin, helps to keep the front rod aligned correctly, especially later on, when you install the second half of the engine cases.
Next up: gearbox comparison and install.