No it's not for the 1954. I've been down that road years ago when I replaced the housings with a 1955 unit, so it's all good. I was looking through my stuff the other day which includes a mixture of 1954 and 1955 gears and wondered whether the gears could interchange. I'm sure I read somewhere years ago that someone had either achieved it or at least tried. As for the rivetting , if the old ones were taken out I would have no hesitation in fitting new high tensile bolts torqued to correct tension with nyloc nuts and high strength Loctite threadlocker ------ provided there was clearance which I have not looked into. And I've set gear tolerances / backlash before and it doesn't scare me.
The '34 ute ( pick up if you like for our USA cousins ) has progressed to it's all painted and 80% together. Main hurdle now is to finish the wiring. 🥺
With the proposed relaxed eg. cheaper state registration fees for street rods and modified customs available in the near future it might spur me on to get it finished sooner.
But it's too damn hot in the shed these summer days and I'm getting less tolerant to it as I get older.