1 is blue / green , 2 black / blue , 3 green , 4 blue/ black , 5 brown , 6 black / white , 7 blue/red , 8 blue , 9 vacant , 10 white/ blue , 11 vacant , 12 brown/white/red , 13black/green , 14 grey/purple , 15 grey/ purple / green . this is from a book printed in 84 [ mb body book ] not specific to a certain model . so use this as a guide , you may be lucky .
you say It's not specific to model , but is it specific to year ? mine is a 1975 450 SEL ( Early 75 ) >>> 11/74 date but 75 year model
What I did so far was to cut one off at a salvage yard from a 78 model and also a 79 yr. model both with about 10 inches of wire . and they are different then a 1975 it seems . Some wires match but not others . Also one has 14 wires rather then 13 . Colors are a bit different also .
I well look tomorrow but your guide looks correct in some respects for sure
as Pin Hole 9 and 11 are Vacant ! .
As I found no Diagram ( where did you get your info ? what manual ) I am in the middle of making up a short wiring extension from the salvage yard wire's I got . Plan is to plug one end to the cluster , other to the Pin Connector then start switching the wires around to see what happens and if I can get it straight .
What I worried about is that I well somehow jump to much power to something ( like the gas Gauge ) and fry it or the Tank Sender perhaps or the temp Gauge .
Note: Everything was working just fine except no dash lights . So I pulled the cluster ( first time for me ) to replace the resistor and unplugged the 15 pin connector to discover the Center Guide Bakelight Pin was broken off and missing ( perhaps inside the Cluster ) and the thing crumbled and all the wires got mixed . But Every single part / Gauge's where working prefect and had I known of this issue I would have never unplugged the Pin Connector and just soldered a jump wire across the Resistor ( I ended up replacing the Resistor from the salvage yard )
Right now some things work and some do not Like the dash lights now work but the gas Gauge jumps to Full . Dash lights come on when you turn on the key rather then the lights . I tried switching 2 wires and then the dash lights worked normal lights on dash lights come on . however temp Gauge reads low temp and Gas Gauge just jumps to full . switch things and no gas Gauge reading at all lol hummm
Thanks much for the help I shall look in the AM to see if your legend seems correct for the 1975 Year Model