My rev counter didn't work when I got the car, I changed the clocks which was a bit of a pain but the MFA wasn't working either so it was worth it, however......
....when I got it all back together, the indicators didn't work and instead the stalks operated the horn! Imagine my surprise!!!!
Seemingly, it's really easy to slot the flat pins into other sockets so be aware of that. Bear in mind as well that if you do have to change the clocks it is a dash out job and it's really easy to break stuff as I found out at a cost!