I'm not a big fan of this swap any more. Versailles disc brake parts are getting hard to find and $$$$$. Plus the rear end is very heavy. Used to be this was about the only way to get rear disc brakes but now there are lots of other, cheaper options.
the versailles parts are actually getting easier to find, teh aftermarket is now making pretty much every part of the brake system including the hard as hell to get parking brake levers on the caliper. you can get everything you need to rebuild the brakes on a versailles rear end from autozone even, if you so choose. it is still a popular upgrade especially for guys who had 6 banger cars originally oe even anyone wanting a 9" to replace the 8". yes, it is a heavy rear and i can say that from experience, trying to lift one of these into the back of a pickup with just 2 guys is a back breaker.
I'd do the swap and you are right, just get backspacing right on wheels. I'm not sure where the spring perches are on the Versailles, but I swear someone told me this is an easy swap.