Didn't mean to be mean here. I know that searching for various key words will bring up threads that are sometimes years old, posted by vanners who are no longer active on the site, but threads that are still very relevant and contain some very good info. It increases your chances beyond just the active members today. I didn't know you had already searched.
Sorry if it came across as an attack of some kind. It was meant as advice. I've been here a long time and I sometimes forget that I don't know everybody on here and they don't know me. Maybe we can meet at the Nats or Keystone next year and turn up a cold one or two.
There's some 4x4 conversion threads here. Maybe they're not much help other than the pictures of the cross member attachment points.
As far as I can tell (I have two G20's and a G1500) the G20's and the G10/G1500 are the same unibody. The suspension/cross member bolts up the same and the measurements, as close as I can take 'em, are the same. I have no experience with the G30's other than just driving 'em.