OK, here goes:
The power amp you refer to is for the Premium OEM Ford/JBL system from mid-90's luxury vehicles(Lincoln Mk.VII, Mk. VIII, Town Car, etc.) It is a 4 channel amp design based around a pair of monolithic stereo pwr amp IC's ("STK-xxxx" series-Made by SANYO semiconductors, I believe). RMS (And I mean ACTUAL by Pro Audio Standards) power output is somewhere between 27 and 36 watts/ch @ 2%thd (Keep in mind that this is equal to 80~140 watts RMS "Music Power"/Channel by Car stereo standards). Not bad at all, really...
Anyway, if you didn't get the factory cables (or at least the connector plugs that plug into the amp) it will be a real pain in the ass for ADVANCED installers and should probably not be attempted by beginners/intermediates. That being said, here's what I know: First, if you DO have OEM plugs:
The smaller plug(10 pins) was 4 line level shielded signals from the head unit. The signal lines will be the smaller insulated wires that have stranded bare wire shields around them. These you should connect to the center pin of RCA cables from Head Unit, and the bare wires to RCA cable shields. Don't worry about the extra 2 pins. Sorry, I don't remember the exact pinout of the plugs(been a while), to find out, read on...
If you DO NOT have the OEM plugs:
The smaller plug(10 pins) was 4 line level shielded signals from the head unit. Channels are paired: >> Sig+--Shld(Gnd)--Sig+--Shld--etc.<< The extra 2 pins are either gnd or unused (not important). In otherwords 4 of the 10 pins are signal IN+ and the rest should be grounded. A meter "Ohms" test should tell you easily, as all grounds will measure less than 10 Ohms to chassis, and signal lines should be approx. 4K~15KOhms(well, at LEAST 1KOhms to chassis). Anything over 100KOhms should be considered no connection(unused or blown or something hokey). And YES, clever newbies, this method will work for figuring pinout(input) on ANY amp not labeled or marked.
The larger plug (14 pins) next to the fuse is for Speaker outs, B+ Battery12v. , and remote turn on lead. There is NO MAIN GND WIRE in this plug-You MUST secureley mount the unit to a metal surface for it to work! The speaker outs are the 8 pins in an unbroken row across the side opposite the plug tabs(NOT the 3-gap-3 row). Speakers out (L-R) are: Lrear -,Lrear+,Lfrnt-,Lfrnt+,Rrear-,Rrear+,Rfrnt-,Rfrnt+. The BATT+ and REM wires are 1 of the remaining 2 groups of 3 pins (Again, sorry, forgot which one by now) as follows: Starting at the outer pin, the first 2 pins are BATT+12V(both are the same-doubled up to allow for adequate current flow), and will be Yellow #12awg wires on the plug. The next (third) pin is REM Amp turn on from the head unit and is med. dark blue #16 awg and MAY have a blk stripe on it(not sure). To find out SAFELY if this is the REM lead, hook up the B+, Chassis gnd, and at least 1 speaker. Now clip a TEST LITE(with BULB, not LED or meter or anything else) to +12V source and touch the pin with the pointy end of the test lite while listening to the speaker closely for turn-on 'hump' or hiss background noise. The lite will glow feebly and the amp should turn on(listen). This trick keeps damage from occuring if you touch the wrong pin(test lite will be bright, or not glow at all) with batt+ voltage. The other 3 pins? WHO CARES! Just tape off the ends of any unused leads to avoid mega postal incident later when they ground out (They WILL).
**NOTE: Based on total pwr output and output class of amp vs. heatsink surface area, I suspect that this amp will run HOT with all 4 channels driven. Therefore, I would keep impedance ABOVE 3.2 Ohms per ch.(Typ 4Ohms) and consider adding a small 12v. fan if you plan to use the system hard for extended periods of time. (the STK series IC's in the amp have built in protection circuits from; Thermal, Input overload, Output overcurrent, Short circuit-- This makes them pretty tough to blow up, but annoying if they keep shutting down all the time!)
GOOD LUCK and 'Always carry an extinguisher',
splinterhead(Tube and car audio Yoda)
Da Splint- - - Hollywood, CA