I had always heard and read that the front uprights were from the Spitfire. I believe our own JB said it was actually only the uprights from the Mk I Spitfire. I thought I'd check to see what Moss Motors was getting for them and the pictures and listing they show don't look like ours Here's the listing for the upright for 1964 - 1980 Spitfire (
https://mossmotors.com/vertical-link-right?assoc=35350). From the listing for the uprights at Rimmer Bros, it appears our uprights come from the Triumph Vitesse or GT6 and that the Vitesse and GT6 share them as they both share the same part number on their exploded diagrams (
https://rimmerbros.com/Item--i-GRID008048 and
https://rimmerbros.com/Item--i-GRID007840).
It's been a long time but IIRC, when I bought Richard's (i.e. Banks') vented front disc kit, it came with GT6 front hubs. I seem to remember hearing of two different size stub axles. I'm pretty sure I didn't change my uprights or stub axles so I'm thinking that the GT6 hubs are a direct replacement on our stock stub axles and uprights for the stock hubs.
That being the case, I'm thinking that the stock upright and stub axle comes from the GT6.
Can somebody check me on this?