2001 GMC Yukon XL 1500 Question: COURTESY LAMPS

I HAVE A 2001 YUKON XL WITH THE DENALI PACKAGE AND I AM HAVING ISSUES WITH MY COURTESY LAMPS. NONE OF MY INTERIOR LIGHTS EXCEPT FOR THE DASH WHICH WORKS FINE BY THE WAY WORK. OVER HEAD LIGHTS DONT. THE FUSE IN THE ENGINE COMPARTMENT IS A 15AMP AND IS CONSTANTLY BURNING. WE THINK IT IS A SHORT BUT WE DO NOT KNOW WHERE TO START LOOKING. EVERY TIME I PUT IN A NEW FUSE IT BURNS ON CONTACT. IS THERE SOME SPECIFIC PLACE I SHOULD LOOK OR IS IT GONNA BE A NEEDLE IN THE HAY STACK TO FIND A SHORT.