Ariel Owners Motorcycle Club

I have purchased a bike that came with a dismantled cp gearbox. Supposed to be all there but the ks ratchet and pawl are 6 spline and not 4 spline (missing 3/16 rollers and detent spring. I have never seen a CP before so I have a couple of questions.
I have assembled the gears on the shafts in what appears to be how they go When the mainshaft is put in the box and pushed to the sleeve gear the 3rd gear extends well beyond the case If the mainshaft cluster is assembled in the box, there is a large gap between the sleeve gear and the clutch roller flange on the mainshaft (whereas there is only a small clearance with a BA box). Is that gap correct for a CP. There is a large amount of end play .090” to the mainshaft when assembled, however I have temporary assembled with a sloppy on the shaft fitting BA ratchet and pawl which may be a different height. What is the correct end float, for when I get the correct parts. thanks
David

The C box is the same as the BA box except for the size of the shafts, casing, gears and filler plug, all the gear change and k/start mechanism is the same. The end float should be 1/64, ie. minimal but enough to know that the bearings are not loaded.
Your layshaft at least is 1950 or later as denoted by the groove near the speedo gear that indicates the modified ratio for chronometric speedos.
I cannot see anything obviously wrong with the parts but but the C box was used on a lot of other makes so there are other mainshaft lengths although that should not affect the fit of the gears as they should be the same, other than tooth numbers.