hello everyone thanks in advance for your time and effert to help me solve this problem.I have a 1995 ford 250 / 7.3 powerstroke and this morning when i pulled into the drive and turned the key to shut off the truck much to my suprise nothing happend. truck continued to idle just as smooth as ever. So just on the off chance that i made a mastake some where i tride to shut off the truck again. whith the same response. ideling smooth. and right here is where a high state of panice set in. But after about 10 min of high self destruct mode i was able to shut off truck by disconecting the wires on starter selinoid. my question is this how hard is it to change out the key switch and what all is envolved to change it out and what about the air bag . also how do you make sure you even have a air bag. again thanks so much for all the help and info.