02.5 03 g35 sedan

This car is has been a pain, I am installing a DEI 561T remote starting unit utilizing the factory key fob by using the module to detect 3 unlock pules. The problem I am having is not with the remote start module but with the bypass kit. I have used 3 bypass kits now with no luck. 1. 555U, didn't work no matter where I mounted the ring. 2. XK07, powered up, programmed properly, but it would not disabile the immobilizer. 3. New Xpress kit universal bypass, did not work no mater where I mounted the ring. This is an early model (Apr 2002 built date) 03 G35 sedan, they later changed to late 03 model that uses a different ECU. Any suggestions, I am looking at the Fortin CAN-SL2 but I don't want to spend more money if it isn't going to work. Thanks for the help in advance guys.

are you sure your ground when running output is functioning properly?

I was thinking the same thing as installmarc. Those cars aren't fussy at all about ring placement around the key cylinder. Could you hear the 556U click on when you activated the remote start? What if you try the remote start with the key in the ignition, does it work then?