Spitfire axel advice

Broke a rear axel in my Spitfire racer. Replacement comp axel that came with car has no hole for a pin to locate the u joint yoke. I had an axel pull out of an unpinned yoke earlier so I believe the axel needs to be pinned or otherwise secured. Any experienced Spitfire guys have any suggestions? Axel appears to be hardened.

The factory axles use a pin to secure the inner yoke. Many quality aftermarket axles use a bolt through the yoke into the axle. If the U-Joint and flange are installed, it may be hard to see the bolt unless you are looking for it. That is the more secure attachment in my opinion.

Thanks Tom
The end of the axel is tapped and I installed a bolt but the axel can slide about 1/4 of an inch on the splines unless I pull it up against the end of the axel/washer I fabricated. If i do that I am 1/4 in short of having the u joint lineup with differential flange. If I lift the axel and spring it will line up but I am concerned about the ride height being different on each side. Am I seeing a problem where one doesn't exist?

There can be slight differences in axles made by different suppliers. That said there are two axle lengths for Spitfires, the short for the body style with the small tail lights and the long which was phased in for the 71 and later body style. The yoke does need to be fixed in place because the axle is a suspension locating arm on the swing arm suspension. I assume your suspension is still leaf spring and one locating arm on each side from the body to the outer assembly? If it has been modified to multiple links each side then you have a engineering project that you will have to sort out.

You will probably need to measure the length of your spare and the broken axle from flange to the cup on the yoke to see how close they are. They should be uniform but a small variance should probably be OK on a primitive suspension like this. If you are assembling and the axle seems short, either it is short or the bushings the connect the suspension upright to the bearing hub are not moving freely. The upright should pivot freely at the bushings so the axle can move inward and outward during suspension travel. Only the axle length is fixed.

Again thanks. This car has been a complete learning experience. My wife raced one in the 80s that I maintained without many issues. This car was extensively and successfully raced but sat for 30 years until I got it going last year. This car has the leaf spring type rear suspension as you described. If there are other issues I will probably seek out more advice.
Again thanks.
Jon