Hi, just got an old '90 201 thats in awesome shape as a starter to get back into fishing after a 10 year layoff.

Having trouble with the trim gauge and one fuel tank sending unit.

The trim gauge pegs to the bottom when I turn power switch on.

Same with fuel gauge. When turn power switch on pegs to the bottom, switch to other tank reads 1/2 tank. The sending unit is on the top of the tank.

Where to start trouble-shooting these two?