This car used to start easy down to 10 above F, but lately when its colder than 50 F, the starter will dissingage as soon as the first cylinder fires. After six or seven cycles, the car will start, and after the engine is warmed up, there's no problem. Is this a starter-solinoid issue, or is it a flywheel issue?
Check your glow cycle by placing a clip on ammeter around the glow bus cable at the clutch side of the engine. There should be at least 60 amps or so when you turn on the key for glow cycle to begin. If it is significantly less then change all of them out for new ones.