1950 truck chassis swap

If the track width and wheelbase are the same (or close) everything else is just tedious work. A lot of work if you want to try what dwire67 is suggesting, but it will make for a nicer truck.

Bear in mind that in order for the check engine light to work properly you need to use the Dak instrument cluster (no reason it couldn't be used just for the light). The speedometer in the 99 is also electric (it has a motor controlled by ONE or more of the computers...).