I think you would be better off to adapt the expy suspension to have similar capability as the raptor, although as Tom said, you will be hard pressed to gain the same suspension travel without lifting the truck. But I am sure Fox Racing Shox makes a kit for expy's, though not sure if they would still carry them for the older models. ICON vehicle dynamics is another suspension company that I know of. They are geared towards very serious off-roading though. Not sure if their setups (assuming they actually make one for 1st gen expys) would be conducive to use on a daily driver, but some phone calls could easily answer that.