while this sounds like a good idea(in your head) cass. is right, you are up for ALOT of hours in R&D let alone hands on production. Would be more fun and probably cheaper(as wont need to be rego'd engineered) if you made up something like a bush basher, mud racer etc.. 4wd chassis, weld up a body to it, get your running gear sorted, have a blast!
But if your heart is set on cutting up a sedan into a 'ute'(pickup for you yanks) then the oler volvos seem like a common conversion, Certainly less effort as they have a full chassis, blocky body, tops breaks, wickedly sweet steering, and well...As Sven say: 'Ya Ya, its a Volvo, What can go wrong!?'
few pics iv found on ideas:
the write up for the 4x4 volvo can be found here:
http://turbobricks.com/mods/img/art...mages?q=volvo+pickup&svnum=10&um=1&hl=en&sa=N
Good luck with the build noodles, let us know what you decide on in the end!
A rushed choice will be the worst choice.