The IAG interior lights (and Mabett also) tie into the rear crossbar light with an add-on harness (not sure about '25 compatibility), but the nice feature about that is that they can be turned on and off (or disabled - if desired) with the overhead console interior light switched. Previous to this solution, they came on with a door open only by using a very specific wire under the dash. (I had my IAG lights tied into that to start and it was a PAIN to locate and connect). Given that as an option, I would recommend NOT enabling the light. The IAG crossbar connection comes as a separate component for $39 - you may be able to get that and cobble together the connection to your grab handles. I'm actually surprised that it doesn't include what is needed to connect those.