yeah if you have a mach 460 system you would need to bypass it as the amps dont work right with out the oem deck i work for a custom shop and i do all the mustangs that come it is really easy after you have dont like 100 of them. If you want to put a aftermarket deck in just PM me and i will tell you what you need to do.
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2008 Acura TL DD
1998 Beater Ranger DD
1994 Ford Mustang Project