I have a 1989 Ford E150 Club Wagon van with duel fuel tanks. I can move the switch positionfrom one to another ;but nothing happens and it remains on the front tank. Also I do not get a fuel gauge reading when either tank is on.

SOURCE: I have a 1989 Ford

The fuse would likely have more things included than just the fuel guage.There likely is the fuel pump relay in-line too,but that also affects a couple of other things,1 being the ignition coil,and you probably would have no engine run at all,so that's eliminated.Since there are 2 tanks,the guage itself would be the most likely bad component as both of the tank sensors going bad at once is about equal to 1 shot,2 kills.If you ever had a situation where 1 tank would work good with the guage and the other would not,then I would say eventually they both failed.Since you did not mention that,and would definitely notice it,it has to be the guage,if both all of a sudden stopped working.You should check the connection involved first before replacing the guage.A connector or wires on/to the guage.Although it isn't likely that a wire or connector would just disconnect,stranger things have happened,and easily could save $100 or more if it did.Greg