i think you could use a jumper fuse/ wire in the fuse box, extend it, run to the cab, install a switch to complete/ break circuit and viola, you're in business. Only thing is, you will need to make sure your jumper fuse/ wire in the fuse box is firmly secured and won't fall off.
Alternatively, if you're planning to run lights in the future, utilize a Switch Pro 9100, NOT Auxbeams or any other cheap chinese panels - you want it to be 100% reliable, not "mostly reliable with chances of failure" (being a professional wiring guy and outfitter, I've already lost count of how many Auxbeams I had to fix/ replace since 2021. Some people will tell you "I've ran mine for years and it's fine" but take it from a pro, failure rates on those china units are 100 times higher than Switch Pro 9100). Find the "not live" part of the fuel pump fuse, connect the Switch Pro switched output wire there, and viola. Only thing of concern is you will want to confirm the amperage of the fuel pump fuse, as well as make sure your switch pro output fuse doesn't get loose when driving.
either way, doing it that way has its risks that CAN be mitigated, but the risks are still risks. Honestly if it was me I'd just drop the dime on IGLA and call it a day.
PW forum is the HD Rams forum, this is mostly for us peasants (

) with 1500s. i'm only saying"peasants" because i want a PW myself LOL