Steering relay lower retainer is wider that the body is this right?

I just snapped up an old stock steering relay which now has a pull of 19lb instead of 8lb so, on it will go (yes the crappy steering saga still continues). The question is why is the lover retainer wider 67.5mm than the body at 65.5mm. Surly the Flange plate to hold it steady will be an improper fit, or am I missing the obvious? I was hoping to fit an updated CNC flange to stop things swaying around down there.

Check this out
https://www.ebay.co.uk/itm/254941601678?hash=item3b5bb41f8e:g:jCQAAOSwbs5f2IAT

Hi, the trouble is that, that one is smaller to fit the Patten stuff on the market which is a few mm smaller. There is a 65.6mm version but the very lower part of my relay is 67.5 so it wont fit over it.

File it out to fit thats what I did to the steel version I purchased.
A guy I new was selling them in 6mm steel plate but came across the issue of different diameters , I persuaded him to sell me one trimmed it to suit and it has worked great.
Had previously packed the gap in old one with shims also seen an altered original pics attached

Thanks for the pics, I hadn't realised it might need such a large amount of shimming. I am tempted to file the relay end plate down to match the body it would then at least make shimming easier and also give a fighting chance of getting the flange to be a relatively close fit.