What would i have to do to get an 9a gearbox to fit?

I've currently got a FK gearbox in my '84 gti cab. I have been offered a 9a gearbox that should give me taller gearing for the motorway. But from 020 GEAR RATIOS it shows that my FK box has:

90mm flanges, Small switch and a stud mount

while the 9A has:

100mm flanges, large switch and a hole mount.

Get some late model Scirroco or Cabriolet drive shafts , or simply change the flange [GOLF+ latest issue covers this ].

Good article on just changing the 5th gear in 'Tim Styles Golf performance manual' by Haynes ………..

Cheap at Amason

You'd also need to fabricate or purchase a different rear and side mount; and find a hydraulic clutch master cylinder and pipe it all up, etc to the clutch slave cylinder. I think there's an option to adapt a Seat clutch lever to the gearbox, so you can retain mechanical clutch linkage. I think you'd also need a 9A flywheel (heavy!) and clutch; and starter motor.