Model A - layshaft bush

 With the kickstart shaft nearly finished, we need to think about the bush for the lay shaft. This fits in a bore in the end of the kickstart shaft: 

The bush will be a top hat shape to accommodate the end of the layshaft and to determine the end float of the low gear pinion. It's going to be made from this piece of SAE660 bronze:

First job is to reduce the diameter to nominally 1” to pass into the shaft with a few thousandths clearance:

Next, we reduce the diameter such that we have a few thousandths interference fit in the 7/8" bore, and add a small chamfer to aid assembly. That done, we can bore it in steps up to 5/8" - our shaft is 11/16", but we will do that last bore in situ.

Parting off the bush. The hang out here is not ideal at all, and I believe I may have knocked the stock out of square in the chuck - it would have been far better to do this job with the revolving steady.

No matter though, this does not affect the working diameters and we can face off the end of the bush if necessary.

The top hat bush, mostly finished aside from the layshaft bore.

It's not as tight as I would have liked, so I have fitted it with Loctite 603 retainer. This won't be cured until tomorrow.

This is the last job for the lay shaft bush - it's been fixed in place and the Loctite has cured overnight so it is now being bored too 0.6875" for the layshaft. Notice that the shaft is in the fixed steady - it is essential that the shaft is bored concentric to the kickstart bush in the outer gearbox cover:

Some while back I had left a little excess material on the major diameter of the shaft thinking that I might need to play with the first gear pinion end float, and so it proved. As machined the shaft is a little overlength and I used this setup to remove around 0.020" from the end of the shaft which provided the necessary clearance. 

I'm pleased to say that assembly and testing of the gearbox proved that everything works as expected. The next step, and final step, is to machine the recess for the kickstart lever cotter pin.