Which wiring are you referring to? cartridge or RCA/power supply. There is already a thread here; I will link it here below. Maybe it will be useful for you.
My father gave me this week his brother’s Garrard Model RC 210 from the mid 50’s, early 60’s. I have cleaned it and seems to run well. The recordplayer has the original headshell with a turnable cartridge GC8 78/33-45 with two wires (Red/Black) connected to two pins. The other two pins are not soldered and looks not to be suitable to connect with extra wires as these are made out of plastic. It appears to me that this is a ceramic mono cartridge.
The player has a audio cable with a 3-pin DIN plug soldered to a small board within the unit.
Hi. From what I could make out is that you may be having a mono ceramic cartridge on your changer. In this case you need to connect the positive wire to the central pin of the RCA cable and the negative or shield to the outer circular terminal of the RCA cable. If possible send the photo of the cartridge and the rear pin connections. Remember your amp must have a ceramic cartridge input for proper sound. Warm Regards