Agree - I'd even bet it'll get FWD.
But why manual only? Ford have used the Getrag 6DCT450:
It takes up to 450 Nm of torque which is sufficient for the RS.
Many aftermarket intakes are known to plunder power and cause several other issues.
Somtimes better to go with OE parts. There's a "hot climate" intake/filter enclosure,
that can be easily adapted to the TSI/EA888 engine (late Mk.V GTI, all Mk.VI GTI)...
Let's talk about aerodynamics and have a look at serious some sportscars and current Golfs.
("Auftrieb" = lift; "Abtrieb" = downforce)
Some Porsches first:
997 II GT3:
downforce: 152 Newton front and 186 Newton on rear...