Audi 012 gearbox vs Porsche G86.00

I have a Vw Audi 012301211T Passat se diesel 3b5 (1997/2001) on my project if want to switch to a Porsche Boxster 2.5 gearbox G.86.00 (essentially for gear ratios)
From outside seems of the same family of Vw can someone say if flange coupling and clutch splines is the same ?
For everyone I just fit the Boxster g.86.00 and is fully interchangeable with std 012 gearbox included clutch spline. Only gear ratios and output flanges are different