Didn't think you were wittering on Nick, Always interested to hear from experienced people (regardless of the subject) and often my questions are oppositions are that until I find out why... (like needing the end float limited to reduce/stop bearing movement).
I was thinking of screwing it down the case also as you did. From memory the bearing is 27mm, i had a 4mm spacer made up. On hind sight it could have been a couple of mm thicker, more so even, then made with a wider surface area for thurst control.
Do you have any drawings/photos of the work you did, would be interesting to compare ideas (and possibly pinch ideas too )
Nick, Charlie Barnes made a steel insert for the drive side bearing on triples that wore out the bore. Possibly that could be done for your blown out case. An inside lip (DS) for the bearing and an outside lip (TS) for the case.
I see what you mean Dave, thanks for the heads up, I did think about sleeves/inserts of various types but really the route i'm taking is the easiest way. I didn't even need to 'glue' the broken piece back on as it's not doing anything anyway. The primary side will be open to crankcase so no need for a seal, like triumph. I know it doesn't sound (or look) very elegant but it also means that i don't have to farm out more machining to people i am uncertain about. It took me long enough to get someone who would do the line boring and counter boring of the timing side, i don't want to push my luck trying to get stepped sleeves made and fitted too. I've assembled the crank with dummy spacers etc and the old TS bush and all seems OK, so as the new bush is on it's way i'll carry on with it.
Allan, that engine is long gone and i never had any photo's of the setup. It was straightforward enough though. If the OD of your needle race is 47mm (normal one to use) the thrust can be made to just slip over it and run on the machined flat on the crank web. As the race projects into the case the thrust can have a step allowing the fixings with no interference.