As I intend using them primarily to mount 'road' tyres, 5.5 inch is fine (I was going to run 185 wide tyres anyway for autocross, as I have found the slightly narrower tyres cut through some of the looser stuff better...
I agree regarding the 164 rims, maybe they are just the same as the early 140's...
I measured the centers at 334 mm (not accurate enough to do fractions of a mm, but what you say regarding the 337.5 mm rings very true. Ford / Commodore / random Japanese rims that I have looked at at the wreckers all seem to be approx 3 mm (roughly 1/8 inch too big...
Looks like a build up of the inner rim radius by the approx 1.5 mm is the way to go at this stage,
Thanks for the constructive comments.
Here's a few picture of the build. basically working on it full time until I get a new full time job!
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