dual tanks dealer add on

[kglowacky]

just noticed as I walled by my truck bed that the gas filler holes on both sides of my truck are different. The drivers side has a recess where the filler neck bolts to the bed and the pass side does not. I also discovered I don't have a dash switch hole for the gauge switch change in the cab. I do have a two way valve under the seat. I do have both tanks and hangers. Did they come with only one side recessed and/or did dealers add these at the dealerships upon request.