Hey I've done something similar. Absolutely pain in the a** if you try to use the newer harness / coil pack ignition. Just pull your engine harness without damaging it and convert your new engine to distributor. Just pop the cap off the valve cover /cylinder head and bolt it on. Swap all accessories and might as well do a timing belt and water pump before it goes back together. Newer motor had a cam sensor which might leave you confused but it doesn't need as long as your running the older harness/pcm