Need more info, unless you have data recording that the rear tires are spinning from half track on, the only reason to have them is to look cool. Any old pics you see with them on were just used to help the air get over the headers and tires, like the mudflaps you see on current RE Top Fuel.
Generaly to mount them is to have a Heavy wall CM tube going thru the entire wing thru the spars and that gets pinned into a socket welded to the frame. you can also add adjustability by adding another thru tube towards the back and the tube going thru plates bolted to the chassie.
I would post pics put all my files seem to be too big