Found on the net

"I have no idea how old this photo is, if it is from the 1940, 1950s or 1960s but suspect it is not newer than that. If anyone knows more about this photo, this old time Harley rider or the bobber Knucklehead please let me know."

Two shafts, one box

With the engine done it was time to fluff up the gearbox aka transmission aka seized ball of rust.

Good start, the corrosion turned out to be superficial and the seized turned out to be a screw someone had dropped in it.

Tony Bairstow, above, and a bunch of old bearings, below.

Below are some of the parts that needed to be replaced.  Avoiding mumblings about OEM parts, virgin steel and Polish crap I ordered the cheapest repro parts on the net, from Flatland 45 parts depot (USA).

BIG MISTAKE!  They were rubbish, all dimensions out by at least a few thousandths.

This repro gear came parkerised.  I'm only a beginner at this stuff but am pretty sure that if a part spends itself in a box full of oil then it doesn't need to be parkerised.  I'm also pretty sure that parkerising increases all dimensions slightly and it doesn't fit.  At all.

Hours were spent filing and emery paper-ing to turn the black bits shiny.  Also smoothed off all my fingerprints and was left with approximately 2.5 fingernails.  Then I noticed that the dogs weren't even undercut so ended up putting the old one back in.

After much massaging and sanding of washers we got it all together and... the damn sprocket didn't fit.  Thin taper on the repro shaft resulted in the sprocket hard up against the case.  Beer time.