Have you tried some starting fluid? Use it as a tool, if it fires and dies, then its probably a fuel problem. If nothing happens, then its an ignition issue
Are the engine computers compatible? Are the spark plugs wires connected to the coil in the same order for both engines?
Have you checked for engine computer fault codes (key on (til idiot lights come on)/key off/key on/key off/key on)? They will show up on your odometer display. Hope this helps.
