107 380sl fuel sending unit
 

I replaced the light in the instrument cluster. Now the fuel guage doesn't work. It reads empty and barely move. I suspect is the fuel sending unit, where can I find the fuel sending unit?
thanks.

It lives in the soft top storage area under a white plastic cover.

Thanks for the info.. I should've check the maint cd first.. It looks like the sending unit is all gumed up.. The car was sitting in a hanger for the past 3 years.

I've seen several people state similar problems after removing the instrument cluster. Breaking a ground connection seems to be a common problem. You might want to check for that.

The gauge went back upto 3/4 full (it should be full tank). I check the ohmage between the terminal G & T (83 ohm) and I put 20 miles on it and now it read 31 ohm.. I will take the sending unit out and clean it once in for all.. Thanks for the advice...

Well, it turned out it was not the sending unit afterall. Check the ohmage and I did see it change. I attached a pot to the plug and adjusted the pot and saw the gauge from full to 3/4 smoothly then it just poped to empty and jump back and forth to 3/4..
That lead me to suspect it is the gauge.. Now I will try to attach another ground wire to the cluster and see if that help..