Cap Wiring for 2005 Crew Cab

I purchased a 2005 Silverado Crew Cab Short Box. I aaded a Cap to the bed and would like to have the cap interior lighting to the bed light switch. Any sugestions where to connect on to that wire to the bed light. Thanks.

William L. O'Neal wrote:
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I connected to the back of the mbec where there is an extra power pin that is used for the cargo lamps in the Avalanche and Escalade EXT.

What is the mbec? Will this pin allow the cargo light switch control the cap interior light in the cap? Also where exactly is the connection point? Thanks for your reply.
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I corrected your posting, please fix your news reader so the thread will make sense when replying.
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mid bussed electrical center. What we used to call a fuse box. The one under the dash (well attached to the floor) has these connections. You will want the schematics for reference http://www.gmupfitter.com/publicat/2004_BB/2003_Beyond_LD_Electric_CK.pdf Page 259 you see C11 of C1 (C1 is the large plug on the back of the mbec). get a .260 female metripack pin and plug it in there for the power source, run this to one side of your lamp. Then go to Page 262 and you will see pin A2 is the where they ground the lamp, I added a wire to that pin and ran it to my the other terminal on my lamp. When this pin is grounded the lamp lights up and turns on the indicator in the gauge cluster. By just running these two wires to your cap light it will be controlled by the cargo lamp switch. Then take from the side connected to A2 and run that to a switch and the other side of the switch to ground. Then that switch can control the lamp as well.