friend needs one for his 71 Challenger and I can't seem to find anything...anyone have a lead?

There are no relays in the system as far as I know.

I build a kit to put relays in the doors/quarters that take load off the switches.

The only thing extra is a big circuit breaker/ fuse in the driver kick panel.
no relays.

the number is 2926433..its listed as a power window relay...I had one on my 70 Charger and I gave it to him to install on his Challenger to diagnose if his is faulty or not...this is the relay in question

learn something new and all that.

This guy converted
http://www.ebay.com/itm/Mopar-1968-1969-1970-1971-1972-1973-Charger-Power-Window-Relay-Upgraded-Style-/311878087593?hash=item489d61f3a9:g:D0YAAOxy039TOGPs&vxp=mtr

or
79 parts book it would be a part #3879696.

http://www.dpmotorparts.com/list_parts.cfm?page=339

https://www.cjmotorparts.com/nos-mopar-parts-inventory.html

https://bradsnosparts.com/inventory/page/1267/

Jim

This is what I used on my 69 Charger factory power window setup.

Napa AR200 relay.

http://www.ebay.com/itm/Multi-Purpose-Relay-NAPA-AR200-/331930704862?fits=Make%3AFord%7CModel%3AMaverick&hash=item4d489c9bde:g:iC4AAOSw-0xYmKPw&vxp=mtr

I think that is the relay that disables power to the windows when the ignition key is off. I wired a switch into the relay ground path so I could also lock-out the windows when driving so the grandkids can't mess with the windows.

The door relays are a good upgrade as they take the current load out of the door switches which are getting pretty expensive.