Disco 3 manual gearbox

[philt]

Hi all, I am looking for someone with experience of the 6 speed manual gearbox as fitted to the Disco 3 tdv6. I think this is a ZF box similar to unit used in the BMW 330d and others .My question relates to the torque capacity of this box. The LR manual states the torque capacity is 357lbft whereas BMW quote 420lbft for the 330d version. The reason I am interested in the LR box is I want to use it for a diesel conversion behind a Merc OM648. My concern is the Merc make 370lbft standard and I would be looking to chip it up slightly as well. Does anybody make an upgrade for this box to increase torque capacity?Has anyone chipped their Disco 3 with the manual box and did it survive? Are these boxes known to give trouble in normal service? Any thoughts or comments appreciated.