Old--uhh--VINTAGE--cars tend to wear out. Or break stuff. On vintage Saabs the ignition keys/cylinders/locks get tired and finally head West. New Saab parts are NOT available, so I engineer good quality replacements that work well and are reliable. In the case of the Sonett III cars, you have it easy. All you have to do is get rid of the housing that carries the key cylinder AND the steering column lock mechanism. It is a pain in the butt anyhow. Saab 96 & 96 cars are even worse, but I'll talk about them later.
Saab used snap off bolts to hold the mechanism to the Sonett III steering column. I use a very sharp small chisel and ball peen hammer and back those bolts out. It is easier than you think [see drawing above]. I have a very good replacement system for the Sonett III cars, which bolts quickly back into place, right where the original assembly sat.
I refuse to install anything I don't test first. Above is the simple test rig I use to make sure I have the replacement ignition switch system wired correctly. The bulbs light up as I turn the new switch to it's "ON" and "START" positions.
The switch is in the "ON" position here. Current is flowing through the heavy wire that will feed 5 fused circuits in the Sonett, as well as to the coil circuit for running the engine. I got that one wired correctly--HA!
This is the prototype replacement switch/relay/wiring/mount assembly for a Sonett III. It would be rotated 180 degrees to mount in an actual car. Once in place, all you have to do is pull the wires off the old ignition switch--one at a time--and plug 'em into the [well marked] wires shown here, and you are good to go. Pretty neat, eh?