ignition switch problems are a PAIN. you can do what i'm doing..
in the 924/944, the #50 and #21 (working from memory here) current tracks can be switched on to activate the starter. wire in a nice $5 pushbutton and mount it in the cigarette lighter location.
well, i'm wiring it into a race car, i don't care about the "originality" because the car is being rewired. however, i have seen the push-button starter mod done to 911s before. matter of fact, i got the idea from a guy with a 911
in any case, push-button or new switch... good luck!
obin