Ford Repair: 87 ford thunderbird, ford thunderbird, vacuum leak

Question
QUESTION: i just replaced the spark plugs on my 1987 ford thunder bird and now it starts and dies right after. i checked the fuses and their all good can you please help

ANSWER: look for vacuum leak-dirty throttle bore and or maf sensor
make sure breather tube is not rolled under on throttle bore and sucking air. also make sure tube to side of inlet hose is connected.

---------- FOLLOW-UP ----------

QUESTION: everythings good their but now ive hit the issue point the only way to keep it running is to hold the key turned alittle past run and it will run i had to drive it from my friends house back to mine while holding the key forward any idea what this may be?

ANSWER: its the ignition switch it is coming apart. use a good quality one to replace it stay away from the zone

---------- FOLLOW-UP ----------

QUESTION: ok i got the switch but its still doing it bought the part from napa

Answer
if it will run if you hold the key on then it has to be in switch or linkage to switch-make sure it is properly adjusted-the two forward positions when you turn the key is first position run-second position start so if it will run in start position that means the the key is having to be pushed further to engage contacts which supply voltage to coil and module in run position-does the lock cylinder feel normal when turning it?