I have recently acquired a relatively rust-free 1979 242 that was brought from Washington State to Michigan by a college student. I really liked driving it, so I took it to my mechanic to get it looked at to address various deferred maintenance issues. After a couple of weeks in the shop, it has received a new clutch, various engine and transmission seals, front struts, front brake rotors and calipers, etc. The one issue that is still under consideration is the overdrive. The transmission is a M46 that appears to be newer than the car itself, and the shifter itself only indicates 4 speeds and appears to be a shifter for a M45 transmission. There is a nonfunctional toggle switch zip tied to the side of the shifter shaft that appears to be an attempt at an overdrive switch. I wanted to go for the newer click type shifter knob with the relay but my mechanic wanted to keep things simpler and more period appropriate with the sliding type knob. However, we are currently stymied as once he pulled off the current shifter knob, he looked down the shaft and saw a solid plastic plug rather than one with a hole and grommet for the OD wiring to go down. Do I have to find a shifter shaft from an M46 transmission in order to continue with this project? If so, where might I find one and how much might they be? The salvage yards around here don't have Volvos, and the online sources that I am familiar with (IPD, FCP Groton, Volvoworld) all have knobs, switches, and relays, but no shifter shafts. I'm not really wanting to buy a whole M46 transmission for this one part (and wiring harness, if available). Am I spinning my wheels for naught? Can I just drill (or have the mechanic drill) a hole through this plug? It seems a bit silly that this little item is keeping the car in the shop.

P.S. I don't have the paint code handy, but the car is a really solid minty green color (think Menthos). Does anybody have an idea of what this color is called? My wife just calls it ugly.