Hi Pete,
I recently have pieced together a set of forks for the 8in. single sided hub,
The bottom sliders that take the stepped spindle are the difference, the stanchions and so on are the same for A and B models
Several different BSA models use these sliders, including B31/33's some A65/A50 and B44, models
The unit construction model forks may even have the 2 way damping
Gold Stars and B31/33 models 49-53 dont have a steering lock fitted to the top yoke
the part numbers for the yokes are, top 66-5088, bottom 66-5089
Clubmans bottom yokes have tapped holes to fit bolts to limit steering lock are number 42-5015
same through to the DBD models,
The late Goldie top yoke (CB32 7001onwards) is part number 42-5011
these yokes have a number cast into the underside, (unique to these??)
The later A and B top yoke with lock hole will fit the non lock frame
I'm not sure if theres a difference in trail angles with the different yokes or not ?
If its of any use to you I have a newly painted set of 54/55 B33 yokes for sale
Regards
John