For the TGP, go into AG mode and I think OSB 1 (one that says options or settings or something similar) should open up a settings page. On the left hand side there is LSS and one that says something else to do with the laser I think (this sets the code the laser fires on, not what the TGP searches for). Type 1688 or whatever's needed in the UFC or CDU and click the button that says LSS. This will change the code the TGP searches for. 1688 is the default so I doubt you'll ever have to change it with AI JTACs.
This is just my recollection, I haven't used those settings for ages.