The wheel spindle, fork legs, brake shoe carrier casting, inner hub and any other gubbins should be regarded as one piece when tightened up, only the wheel and brake drum should be free to rotate. That said the fork legs should not be strained inwards or outwards when the spindle nuts are tightened.
To be sure I think I’d let the air out, fully compress the forks and then take a reasonably accurate measurement, + or – 5 thou should do. Measure the spacing at full extension too, hopefully it will be very nearly the same, if not you are fully authorised to first beat your breast and then panic for in that case you are into quite another ball game!
If there is a big enough difference between the fork legs and the wheel hub width then you will need spacers. The most critical measurement, the “worst case” position, is the fully compressed one because in that position there is the least tollerance to misalignment, use that one if there is any doubt. I’d expect the wheel to be equally disposed between the legs but the Mk.I eyeball, a length of string and a correctly positioned rear wheel will get both wheels nicely in line.
If you need spacers and can’t make them, scribble the dimensions on a fag packet, (preferably a full one), and I’ll knock a couple out for you.
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