I just ordered the stock VFR top and bottom bearings online (hdlparts.com) and they are the same size that will fit on the 954 triple. Sorry I don't know the exact sizes, but if you look up on allballs I think they have the equivalent tapered roller bearing part numbers that will fit as well if you want roller instead of ball.
I am not sure what you're asking on the second part about the yokes, for the height of the forks above the top triple I set them just below the blue cap and made sure that they were even by sliding the axle through.
Also with the stock body there are at least three issues that I am aware of: dashboard clearance, oil radiator interference, and inner shroud/wind deflector clearance.
The brake and clutch reservoirs/master cylinders will not fit with the 954 clipons and would hit the dash since the clipons have to go below the top triple, this could be probably fixed with some tall helibars. The front forks and lower triple will also hit the oil radiator and oil lines, this can be temporarily fixed by moving the radiator to the lowest hole in the upper stay, or a better/more permanent solution is to put a slight bend in it and curve it away from the forks. I just discovered the last problem this weekend, the inner U shaped shroud will need some cutting away at the top which shouldn't be very hard at all, and won't effect any of the tie in points.
Hope this helps, have any more questions post them up
Ok im off to garage now to try out the vfr bearings i have already. Hoping your saying the vfr bearings will fit on the 954 stem. will soon find out.
Ill also take a few picks.
Had same project on table over two years now. Just picked up a decent '95 engine and parts so now have good donor. But my last blade front end project has been so good that i havent needed to upgrade.