I have built a rotary powered Triumph Spitfire autocross car, using a 2nd generation RX7 differential and 1st gen (1.6) Miata rear suspension uprights. I had to build my own custom axles by splicing RX7 inner CVs and 1.6 Miata outer CVs with a welded together shaft due to the different spline diameters and have snapped one in two for the second time.

My question is two fold:

1) Can the 1.8 Miata rear wheel bearings and hubs be used in 1.6 car rear uprights, or will I need to swap everything? This would, as I understand it, give me the large spline CVs on both ends of the shafts. I'd like to keep the 1.6 brakes for clearance reasons.

2) Who out there machines custom CV axle shafts? I need them machined from a solid steel piece, there's not enough clearance for a tube shaft.

Thanks in advance.