I just did the keyless entry while car running hack and it works good...
I have a remote starter piggybacked on to the keyless entry system so whenever I remote started the car I had to use the key to get in.. also the remote starter had other features that were blocked because the keyless entry system was dead whenever the car was already started...
I used these instructions...
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I didn't put on a switch, I just taped the ends, I'll be soldiering a switch on next weekend.
The instructions on that page are pretty clear didn't have any problems. It might be handy to have a flashlight handy though since it's pretty dark deep under the console even in the daytime.
--Mike