He is NTL if i remember correctly so netid will set itself for him. As you said all he needs to do is pull red jumper and set pin in eng menu. Netid will reset itself when he plugs it back in.
If you take lid off box you will see a tiny wee red plastic cap. Pull it off and leave for 2 mins or something. Put it back and go into eng menu and choose your pin, i think to confirm it you then press services on the front of the STB.