Checked that today, still no spark. Here's everything I've done so far...

Checked resistance on the coil, pickup coil and cables. All are good. Checked power to the ingnitor and to the coil when ignition is on and power is there. Cleaned all of the connections and ground contacts. Replaced the distributor and cap. Checked for spark using a timing light on cylinder 1, by holding a spark plug to the block and by holding the high tension wire close to the coil while cranking and in all cases not getting a spark. Checked and cleaned the ground connection on the engine block. Also used the 1.5v battery test on the ignitor and got the right voltage change at the coil.

I'm completely out of ideas and about to resign the truck to the mechanic. Can you guys think of anything else? Thanks