I have found a source for the 10mm AP princess 4 pot upgrade spacer kits. The spacers are £28 +p&p or the kit with bolts and seals is £40 +p&p. Available mail order from someone called Mal at MCVator@aol.com.
I have a set of 4 pot princess calipers, waiting to be fitted,to an 82 taz, but are in need of some work, is there a rebuild kit i can get? Do they bolt straigt on to granny parts or is that subject to alteration also?