Electrical fault?

Machanic changed gear lever rod and now my electrics have gone hay wire, when i accelerate the lights flash/heater won't work the same time as the windscrean wiper, I was told that because the machanic did not take of the alternator off this is the result. some say a wire has come off. can anyone help as I have spent a fortune already on dodgy machanics.

Danny Williams
February 2007