Thanks for your replies.
Here's a small update:
The speedo works, but above a certain speed the speedo starts jumping and there's a loud buzzing/grinding sound coming from directly below the seat. I'm assuming that it's the speedo drive housing. It's slightly cracked so I assume the resistance from the speedo pushes the housing outwars just a bit, resulting in the gear grinding over the worm gear in the torque tube.
Removing the speedo cable solves that, so I'll order a new housing among some other parts while the car is in hibernation.
The gas gauge got a makeshift repair with liquid sealant because I don't have the gaskets stocked. I'll order new cork gaskets and coat them with gas resistant sealant before installation. That way they should last longer than the last one.
On top of that I lost almost all power today after a short trip at about 50 mph. Turns out that it wasn't a hanging float like I'd assumed (that has happened the first day after a sharp and fast left turn) but the small bakelite plate that opens the points-finger. Almost completely sheared off, it probably got brittle with age and just broke off. After trying to fix it with what I had with me (and failing miserably), I screwed the contact point all the way in and limped back home in 3rd gear at low revs. But at least I made it back without a trailer, so that's still something positive.
Total statistic so far:
Runtime: ~4 - 5 hours over 3 days
Traveled distance: ~ 34 mls
Number of breakdowns: 2
Number of curses: 0 (a wonder!
)
Lessons learned: Keep the tools in the car and ALWAYS carry some duck tape.
Have a nice day,
Daniel