It won't start

I have a 1988 Bronco with a 93 302, a 94 e4od, and a 91 rear dif and a 88 front dif I know sounds like a country song but It has 33's ss tires. It wouldn't start one day I changed the alternator the starter the solenoid the ignition switch the ignition lock cylinder the wiring to all points listed and yet it still will not start the only thing I didn't change was the ignition actuators in the steering column. So I ran a push button in it and now it starts right up every time I would like to know what is wrong with it any ideas would help. It won't even turn over when you turn the key it would do nothing no sound nothing but all the lights on dash come on like it is going to start but when you try to turn over its nothing. please help thanks.  

there is a problem with the ignition switch. when you turn the key to on everything works fine. The problem exists when you turn the key to the start position. the circut has a short in it or is not closing to engage the starter.  
'91 K1500 (Stock)
LT285/75R16
Play hard! Play soft! As long as you are having fun!

I bet the two adjuster screws on the ign switch loosened and the switch slid down. It happens allot. It is located on top of the column above the brake  

three things could be wrong. Either the short mentioned above by RealEstateDan, or the Key tumbler itself is broken, or the rod that runs down the steering column that has something to do with the starting of the truck is bent. This was bad on my 1990 bronco. My key was hard to turn and when I forced it, I bent the rod. So when I tried to shut the truck off it wouldn't. Once i got it to shut off, i couldn't get it started.

SO turning the key actually does nothing, or is damaged so it doesn't turn enough to start anymore. Under the key tumbler is a small hole in the column..turn the key and push a safty pin or something in there to depress the pin. The tumbler should then slide out. The end of the tumbler should look like a miss shaped t. If that looks ok..look inside where the tumbler was. Look for any damage. If that all checks out fine, your looking at a pissible short, or broken column rod (don't know its technical name).

Hope this helps.  
1995 F250 HD 460BB C6 68,000 miles

also...if turning the key doesn't allow you to push the pin in, your tumbler is bad. Napa sells them for $15-20. A junkyard may just give you one.  
1995 F250 HD 460BB C6 68,000 miles