I have had issues getting these engines to run even after doing a simple cam belt replacement. Have you tried leaving the distributor cap a little loose and tweaking one way and then the other. It doesn't take much to prevent these from starting. Also if you haven't done it already, you may want to consider pulling the distributor and running the oil pump a while with a drill to make sure there is still oil in all the right places. I made a makeshift large screwdriver out of a piece of metal dowel to run the oil pump, worked great.