Well, first check your fire (if you havent done so)by pulling a plug and have someone turn it over while you look for spark on the sparkplug. You will have to ground the sparkplug against something metal to see if it has spark. If there isnt you have to trace back through your ignition, checking wires, checking the power lead to the distributor, the distributor itself (let a mechanic check this out) Then if this is all good it could be your switch in the cab. many possiblities. But first I would rule out the spark question. Thats all I have to say, anyone else?