64 Ignition Switch Wiring Help

[Johnny Too Bad]

I recently bought a new ignition switch for my 64 Chevy (350 sbc with alternator) because the one that came with it was obviously not the right one. It didn't fit properly in the mounting hole and would turn freely when I turned the key.
When I tried to wire up the new switch I purchased from Classic Parts, I realized there weren't enough wires. The PO did a major hack job in the wiring dept (along with most everything else) and it's been a nightmare trying to figure out his wiring scheme since he basically used all red wire.
Anyway, as you can see inthe picture, the switch I took off only has four posts (battery, ignition, accessories, ground) and the new one has five (batt, ignition, solenoid, acc and ground). The problem is that when I wire it up it, everything comes on, but it won't crank over. I had no problems before, and I double checked the wire from the solenoid s post to the ignition switch.
Wiring is probably my weakest area and I'm trying to learn as I go. Any suggestions on how I can fix this, short of re-wiring the entire truck?