help with switchbox idea needed

ive got this cool looking skull ima use for a switchbox in my truck (i know alot of people use skulls for switchboxes). ive got a pre-existing switchbox already (AVS 9-switch switchbox) and i THINK i can tap into that for the power portion of it. now i only want the switches in my truck to have the following:

front: 1 switch total for both sides for up/downback: 1 switch total for both sides up/downpancake

basically only 3 switches which is probably about all i can mount on the skull and have room for the wiring. would i be able to tap into my existing wiring to do this. i want to be able to use my AVS box for daily useage but use the skull for show purposes. also, im not sure what kind of switches to buy exactly to do this. i can do the wiring myself, i just need to know if tapping into the current wiring and what-not would be fine. thanks for the help and im sorry if this is a dumb question.

why not cut your avs switchbox cable off somewhere unoticable get a plug from a wiring harness and then just unplug the av and plug in the skull when you want to use it

you can get switchbox cable from suicide doors.. i wired up my skull myself