Gauge Swap wiring help
 

I bought a gauge off of an 87 turbo truck to put into my 88 4runner (I wanted the tach. and the engine gauge insted of dummy lights) I tried to just plug it in but that didnt work so I looked at the wires from the new gauge and compared them to the ones in my truck, looks like I have most of the wires they are just in different places. I have 1 extra Wire (green-red) according to haynes this is a back window light (dont care if I have that) I also have a brown wire where the truck had a white-black wire (in Haynes it looks like both are ground wires so I think they should be interchangeable) and I have a red wire where the truck had a yellow wire (haynes dosent have any yellow wire listed in the diagram) anyone know what this wire could be?
sorry for the long post...

Well I got the guage working (looks like the red and the yellow were interchageable) but now the temp gauge seems to run a lot hotter anyone know if the temp gauge on the turbos were different than the non-turbos?

Don't know so I thought I'd give a bump.

Well I looked up the sending units and it looks they have they are the same, now im thinking ether this gauge or my old one was screwed up. Im thinking about geting an aftermaket water temp gauge, but I have a few questions:
1. Could I wire it to the stock sending unit?
2. If not how hard would the install of the sending unit be?
3. Are most aftermarket gauges accurate?