rear cab light wired to rear maps??

[BIG JUICE]

Hey guys, did a search but can't find it.someone posted on here before a way with a resistor to wire the rear map lights in with the rear dome. Any ideas/instructions? thanks!

 

[BIG JUICE]

found it on another forum
http://www.ford-trucks.com/forums/1284484-crew-cab-interior-light-mod.html