To be completely "Wheelarched" is to be so drunk a person will attempt to enter his/her car via the wheelarch.
A person i heard of recently had so much to drink at Dinner that after collapsing and then later recovering he then attempted to enter his Range Rover via the space between the front wheel and the car body, he was infact totally wheelarched.
by lordsnootyofspout January 17, 2011