OK, I'll try this again after my text I spent a while typing just disappeared!
Watch the loading if you have the S/R. The relay DOES NOT supply the motor current (in the 03 & later anyway). It supplies the controller / modes. If you want to source more RAP current, I would tap on the black wire (755) to run another relay coil.
For those without a S/R, (including me) Tap the BCM as you see in the upper left of the previous schematic. There's likely no wire there or a terminal. Use a 12089649 terminal ($.88 ea. list, but in a 10/bag), if needed.
Note that I hadn't checked if this is an unprogrammed or "dead" output in trucks without a S/R! So, remove the panel under the steering column and access the Body Control Module. (it's a short way under there and to the lower right side of your st. column.)
If you have power there in IGN & ACC (and RAP if you could squeeze under there and check it with the door shut!) If there's 12Volts, proceed...
Place that terminal in B3 of connector 2 (Gray). It would be between a white, and a Light Green/black wire (either empty, or the dark blue wire). Run it to the relay coil of a standard SPDT automotive relay (even Radio Shack has these). Place a 1KΩ resistor accross it's coil; the other end of the coil needs a secure ground. Hopefully you know what to do with the rest. Wire that relay similar to the one for the S/R relay, but in this case, for your device(s). Just remember to properly fuse from what you're sourcing the relay contacts with!
This relay will klunk when accessories power up and when the RAP dies. So choose it's location for more silence if you wish. Maybe pipe insulation will work. It wouldn't bother me, but may annoy others...