In this case, buy it, take the front end out - the whole she-bang. Put GTST K-frame blah blah blah and put in VG30 + box, modifiy the tailshaft to suit.
LOL at engine out for oil change.
Also, don't bother putting a 26 in gts4, easier to buy a GTR.
But buy a gtst and dump VG30 in, less headf**k than trying to make it 4wd if you want to be different.
And it's a waste of time to import anything unless it's really rare.
By that I don't mean 'immaculate' r33 gtst, but say one of these newer Toyota mark 2 or something you don't see often.
In the end of the day, it's worthwhile if you enjoy the job.
For me, I'm not picky as I desperately want to leave Coles so anything better than domestic is a bonus.