fwiw the honeycomb mag wheels I have for my 1200 coupe (which still has stock 1200 coupe front discs/calipers) won't clear due to the steel 'plate' (that slightly curved thick bit of steel) that the caliper sits inside.

They hit by a good 5-10mm. Another set of wheels I looked at (I actually bought the honeycomb ones from the same bloke) didn't clear either, and it was a much worse clearance overlap than with the honeycomb ones.

So it's entirely possible you've got stock brakes on there, and this is one of the issues. I'm going with the early s13 silvia (the ones with the ca18 motor, so they'll fit under 13 inch rims and have the original stud pattern)

I haven't got them on there right now. BUT I do have a couple of coupes here right now (one is a rolling shell) so if you need, I can attach the adapter brackets and s13 disc/caliper onto a rolling shell, and show how it fits (or doesn't fit, relatively speaking) I'd be able to do it this weekend and upload pics if you need. Let me know, as I won't worry about it if it is no help.