91 Bonn clicking noise and vibration at idle

Me and my 91 bonn have gone through a lot, of repairs and scary moments that is. So perhaps I get overly nervous when I hear a clicking rather frequently (once per minute sort of) with a slight movement in the RPM indicator (up or down) and vibrating very rough when stopped at a red light, to the point that I am afraid it is going to cough and cease, but it never does that. Twice it shut down on me in the middle of the freeway at over 60 miles/hour. Everything locks up, so I don't know how I am still alive. That was the ignition module, which seems to melt within a year. So far I have had the spark plugs, Ignition Module, cam shaft, crank shaft, cam magnet, fuel filter, fuel tank, fuel pump, timing belt, trans service, trans kit, catalytic convertor, alternator... all within a year's time.

Should I keep worrying?