does anyone know how this can be done? preffrably cheaply!
has to fit discs and calipers inside a 13" rim cause 14" rally tyres wil never fit in 1200 gaurds legally (as far as rallyings concerned)

Well... FWIW, 280ZX vented disc brakes will fit inside SOME 13" wheels, but not all. HTH

okay,heres my question,what size discs are you looking for ,252 mm (10') or 270 (11).old dunger pintaras have approx 250 mm vented discs,could be worth a try on some 13 inch mags.OR go to the ozdat site & check out the datsun 1000 disc brake conversion using laser vented discs & calipers.the conversion could be done to a 1200 if you use sedan or ute DRUM brake front struts,& drilling the mounting holes to suit the spacing.also,use your 1200 coupe hub,which uses the same wheel bearing as the sedan,1000 etc,so you don't have to build up the hub with weld.you then just bolt the bugger back into place without having to change lower control arms,caster rods,steering arms& tie rod ends.hope this helps. oh boy so near & yet so far.the conversion is at www.datnet.org in the technical section by dattoman.my excuse is i linked to it through the ozdat site.give it a read i suppose,or the posting under 1200 struts about commodore brakes,might be what you need.