There are 3 "easy" (using factory bits) brake upgrades depending on what strut you want to start with.

1600/180B - A smaller stub axle than most other Datsun stuff, unless you get the late model 180B stuff, which is better. The caliper bolt spacing is 78.0mm, which Commodore or Volvo 4-spot calipers will fit on. Can be used with a Verada disc machined down from 24mm to 22mm thickness.

200B/240K/Bluebird/C210/R30/R31(non-GTS) - The caliper bolt spacing is 89mm, which is Hilux or Landcruiser calipers. Once again with a Verada disc? Does anyone know which is Alloy and which isn't and they both 4 spot?

DR30/Z31 300ZX - The caliper bolt spacing is 100mm. There are plenty of calipers that share this bolt spacing such as R32 300ZX, R32 Skyline GTST, S15 Silvia. But thing to watch is the discs got progessively bigger (and hence the caliper wider). Apparently if you get the R31 Skyline GTS hubs, they will go onto the stub axle, they are a disc of hub arrangement. Then you can get the R32 disc, which is 280mm x 30mm, get it redrilled to the 4 stud pattern and that should go straight on with the R32 Skyline calipers (alloy 4 spot).

Other things to note.
All the bolt spacings on the bottom of the struts are the same. Does someone know the exact measurement? Whatever it is it's the same as some early Mazda stuff.
1600/180B/200B/240K have a small recess in the strut where the steering arm bolts up to, whereas the remainder have a larger recess.

Dont know about alloy or steel landcruiser calipers but the early model have a solid disc, which i guess would be steel caliper and the later model have vented discs which would be the ones that go with verada calipers.

the set up i am using supposubly works with not TOO much alteration

stanza struts, 180b hubs (now i know they fit), verada discs, rx7 s4 calipers, sunny control arms, recond (new tie rod ends and ball joints, etc) 1200 steering set-up

what can u tell me?