Trim Wiring problem 1987 Merc Outboard 175hp

[NESAR]

Started wiring up my trim today and got most working. Here is what I go so far.

LIGHT BLUE / WHITE STRIPE = Trim UP Switch put this to the trim up relay

LIGHT GREEN / WHITE STRIPE = Trim DOWN Switch put this to the trim

BROWN/WHITE STRIPE = Trim Sender to Trim Gage put this to the Gage located on the motor near the trim pump.

All this is easy so far now here is my big ?

PURPLE / WHITE STRIPE + Trim "Trailer" Switch !!!! What the heck is this? I have the wire for it but don't no what a Trailer Switch is or where it is located on the motor. My trim down works fine on the control but the trim up don't work at all.
I'm a bit dumb so if you can please explain this in detail. I don't know what the parts are called on the motor.
It is a 3 wire system coming off the trim motor all of them are hooked up. If I put power from the battery to trim up works fine same with trim down. I just need to hook up the purple wire.
On my control I only have a up and down button but there are 4 wires as I stated coming off the controller for the trim.

Enough said on this part. This is what I tried so far.
I tried to hook the purple wire to the trim up Solenoid it will only work the trim and wont go all the way up for trailer so I know it cant go there.

 

[NESAR]

Re: Trim Wiring problem 1987 Merc Outboard 175hp

After reading on through the post I found a post with the same question. I have the answer where the wire goes, but I now have a new question?????
On my controller there is only a up and down tilt. Should I get a switch to use for trailer it all the way up and use my controller for trim? or just use it as is? Sounds like they bypassed the trim and only used the one on the controller.