D, people use silvia setups on stock 1200 struts mainly so they dont have to change struts, and get only a small track increase (which is almost the same as a larger srut swap anyway)

was just about to post that link aswell, most of the info on actual brakes wont be of that much use as i wrote it in regards to aussie assembled equiptment
but you can follow the list of stuff that allows you to bolt the large struts in

to get nissan 5 stud in aus we use ford falcon(aus only) front hub/disc on the large struts as they have the same stub axle dimentions so they bolt straight on. so you might be able to find something from a US ford model that will work

otherwise 240, 260 and 280c models have 5 stud and you might be able to use the hubs from one of them. been meaning to get my hands on some just to test that...but not really something i have needed to do

another nissan option is early z31 300zx 5 stud front hubs that may also work
and datsport in aus use r31 gts (i think) 5 stud hubs and these bolt straight onto the large datsun stub axle aswell

lots of people have had custom hubs machined up to be 5 stud and suit whatever discs they want to use also, this is obviously the most expensive option but can work better for wheel clearance as most of the nissan hubs are for a floating disc not the solid mounted one like in most of the early datsun stuff

so you then need to get a disc with a really big offset to get the caliper away from the mounting face of the wheel