Mercury Optimax motor to Yamaha Harness and controls

[Matt1309]

I bought a 2005 Ranger Z21 that was rigged with a Yamaha VMax motor. The boat didn’t have the motor when I bought it and I purchased an Optimax 250 from my buddy.

The boat has all the Yamaha controls and harness still in the boat. I have an older Mercury control box with the 14 pin harness, but it’s missing the part of the harness for all the gauges. Is it possible to cut the 14 pin harness end off and splice it into the Yamaha harness?

I know I would have to make sure the correct wires are connected since Yamaha and Mercury use different colors, but is there any disadvantage of doing this?

Is there anyone who has done this that could tell me what 4 wires will be left over after splicing? What do they control?

Before anyone says just buy a mercury harness and swap it out. I cant afford a brand new one right now and I haven’t found one close enough on marketplace at a decent price.

thank you in advance for your help and knowledge!