Mk2 GTi 8v - Inner CV to gearbox bolt type and size?

Hello, can anyone tell me what size the and what type of bolts they are they hold the inner CV to the gearbox?

From what I can gather they are 8mm 12 spline XZN bolts? Is this correct?

 

You can use 12.9 allen heads too if you get the right length. The thread is M8 x 1.25.

 

Ive been told not to use allen heads because it stripes the splines but cheers for the help