1998 Lincoln Mark VIII Ignition Transponder Chip Key Programming Instructions.

How to Program a 1998 Lincoln Mark VIII Ignition Transponder Chip Key
Step by Step How to Programming Instructions:
Can I program a spare key myself if I have one working key? 
Yes, once you have had the new key cut by a Locksmith use the following instructions.
1. Using an already programmed key that you can start your engine with, turn the ignition from the ON to the OFF position.
2. Within 15 seconds, insert a new key into the ignition and turn it to ON or START. The vehicle does not have to be started. If the key has been coded, the theft indicator will illuminate for two seconds.
3. The key can then be used to start the vehicle.
Repeat until all chosen keys have been programmed. (max=8).
If the key coding failed, the theft indicator will flash and the vehicle cannot be started. One of 3 causes are possible:
The new key was not inserted within 15 seconds.
All 8 key codes have been stored.
The key does not have an electronic code.
Go to ProgramYourRemote.com for key fob programming instructions.