faulty petrol gauge and tachometer

[Martin]

My tacho and fuel gauge doesn\'t work half the time, the fuel gauge just stands still at empty and the tacho just go slowly upwards. They sometimes jump back to normal after a while. Just wondering is there somewhere I should look to try and sort it out? or is it knackered? and is this common on early FD\'s?

I may have to get a external petrol and and tacho put on if I can\'t get it sorted:(