I made a new steering linkage last night.
9/16" x 36 spline to 3/4 DD U joints from Car Builder Solutions. $100 with shipping from UK. Apparently they are used on Ford kit car, I think the spline is also the same on a Triumph.
https://www.carbuildersolutions.com/...splines-34-916
3/4 DD steering spline from Summit
https://www.summitracing.com/parts/hdt-sc-209-dd $30 with shipping. I cut mine to 12 7/8" long. I also had to notch the shaft so the bolt could key into. All done with an angle grinder.
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