Torque of transmission brake plate

[Green Hornet 88]

Does anyone know the torque values for the nuts on the transmission brake to the speedo housing? They look like 'pinch' nuts and I found some info that says the torque is 72Mn, 53 ft lbs? I've torque them to 30 ft-lb, but I'm worried I'll over torque if my information is not correct.  I have a early series 2a gearbox
Cheers Craig

[Green Hornet 88]

Fyi, talked to one of the club members re the torque settings he advised that they should be 'wrist tight', I did this an then checked with a torque wrench and came out to darn close to 25 psi.
cheers Craig