You could do a set up like the once on American Muscle Cars that getthe resto mod treatment: A rear sub frame bolts and or welds in, the set up has the classic upper and lower A Arms like a Formula Car front end........these set ups can be purchased whole so the make economic sense but on our Datsuns you'd have to build it. If you can weld and fab it might be worth doing. Also there are proven pieces for the 1200 leaf spring rear that make for a huge improvement, check out all the suspension stuff on the site.

Tom