Ignition problems

I'm a mechanic that has experience in jeeps, but unfortunately not much with the Presto-light system. Replaced everything. It's in time, has spark, plenty of fuel, even ran a compression test on all cylinders, but for some reason no fire. The costumer loves this Jeep and has completely restored it to show room quality and would like to keep it stock. Was trying to push an hei, but he wants to try all options to keep it stock. Any ideas?