I`ve still been working on this over the weekend with some progress and what I did attempt seems to have gone well.
I first finished off the cylinder and also drilled the steam ports including drilling and tapping the exhaust. I must admit, I tapped the exhaust a little near to the edge than would have been ideal but it still worked out OK – no problems and looks just fine. The steam ports drilled just fine as well, no problem there and the cylinder looks very good. More pictures at the bottom, but this shows the ¼” recess on the cylinder bottom with the steam port drilled through:

Got going on the cylinder covers. I wanted to use my rotary table to drill the 5 holes accurately so I turned to length on my 4 jaw, cut the recess that registers with the cylinder bore and then pulled it off the lathe and transferred it to the rotary table.

I then made some more markings and started to part it off:

Cylinder now finished and so is the top cover. I need to drill and tap the cylinder for the cover but I`m going to use the cylinder cover as the jig to mark out the position of the holes. I`ll do this later when I`m definitely happy with it all

Next job is to do the bottom cover but it tells me that I need to ream 5/32” and I don`t have this sized reamer. Truth is, I only have a hand full of odd sized reamers. I`m reluctant to buy a 5/32” reamer to use it only once but of course the rod going through which is supplied is 5/32”. I`m considering buying a metric reamer set and buying some 4mm silver steel and using this instead!?