Hehehe Duncan
You have to think out side the squre when it comes to Skyline's
You know I build some insane RB series engines at Hills
But my FJ20et donk was originally from a good old DR30 Skyline.
They go in really easy as S12's come with FJ's aswell.
I know of a few guys running RB26's in S12's but the cars balance is all messed up
I don't have IRS in this car as S12 IRS is about as retarted as the old 1600 set up and get's no drive off the 2" of the tread it lays down
I run a 4 link live axle has rose jointed chrome molly trailing arms so I can dial in grip by changing the pinion angle I have also made custom towers in the rear to accept the S13 HSD's
Funny is I only coverted to disc brake rear 2 days ago as my hydro handbrake burst the wheel cylinders during the top 16 battle in Tassie, I still got through to the top 8 battle but couldn't really do much with a brake clamp on the rear line, But hey I still had a go...