I have trooper plus 2" coils in mine from Pro Comp and have wound the torsion bars up 2" and done a ball joint flip to get some camber back, though I needed to add an extra 3mm shim behind the top suspension arm to bring it back in line as I wanted it big enough to get 32" tyres under without a body lift, its funny as my wheels went \---/ rather than /---\ which they should have done with a lift, so I suppose if you get the opposite effect than me you could remove a shim if the ball joint flip throws it out more, though that can increase downward travel that is lost in the torsion bar wind up.
also again, its worth trimming the upper bump stop to gain travel.
I have a coil retainers given to me by a good friend on here Alex here is a pic.

Also a good source for parts in your part of the world is here
http://clubisuzu.proboards29.com/index.cgiIt says Isuzu but covers Fronteras, a guy called Geeves is the local guru, tell him I said Hi
