Has anyone installed a additional tank in there 300SD? My reason for asking is I just purchased a 80-300sd and there is square tank installed in the trunk. I know it not standard as I can see across the entire top and except for an overflow hose there is no access on the top for a fuel gauge. There is a fuel gauge somewhere as when I turn on the key it registers 1/2 full. I am trying to figure how it mite be hooked up. It is a very professional job and you csn tell it was built for the vehicle. There is a sticker on the side " for Diesel only
" I am familar with how to take a standard tank out but I do not want to attemp to take this one out without some idea as to what I am facing. I had seen a similar tank on other website some time ago but can not remember which site. Any help would be appreciated