turning into a dually
 

i have a 1994 f250 with the 7.3 idi in it. it is a single axle truck, so i thought, i have discovered however the read axle is actually a one ton axle, instead of a 3/4 ton. so i am highly considering turning it into a dually due to all of the towing i do, and well, just for the looks, (:. but a few questions. i know i need the dually rims, and the fenders, is there anything else i really need? and also with the fenders, since the truck came with a single axle the gas tanks are of course, in the side of the truck, would i have to move those to the fenders or can i keep them there and the fender fit in between them? the truck has an 8 foot bed. and is ext. cab (dont know if it being ext cab makes a difference). i am making this conversion soon so i need an answer ASAP. thank you. https://www.dieselbombers.com/images/smilies/dash2.gif

Unfortunately I don't think you can just put dually rims on your truck. I believe the rims will contact something on the chassis. The dually axles have different dimensions than the single wheel axles. At the very least, you may be able to use some wheel spacers to get them on.