Since it is a '97, if the RCU has heatsinks on it, it's a MACH unit. JBL units were only in 1996. So you should be good. Ford part numbers have been a really sketchy way to identify an RCU.went to the jy last week and found a 97 sho with the mach system still in it. im trying to confirm if the amp is a mach amp. the number on it is f7df-18c851-la.