there may be an access hatch so you don't have to "drop the tank" talk about a hassle, the gas has to be emptied mostly for that...bolts can be rusted...I can look at the montana to see if there is an access hatch...normally cars are equipped with that..may be under the back seat or in the trunk....recommend that you look for that....does the level read incorrectly? or not at all? there is a sender and a receiver for that guage...are you confident that it's the tank at fault and not the gauge...did you test the output?~
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