1976 evinrude 70 hp outboard trim/run switch

Hey folks, I have recently purchased an older boat and it came with a very smooth running older Evinrude outboard. I'm new to boating so I've been asking a lot of questions about proper techniques and such. One area of confusion for me is the operation of a manual trim/run switch on the side of the motor. I have been told different opinions on when to use it. The boat has a well working hydraulic trim motor attached. So...my question is, when do I throw the manual switch/lever to run and when do I throw it to trim?
PS. I've been searching the forums and manuals but can't seem to be able to find it.

Thanks in advance.

I don't believe that is hooked up to anything if you have the factory hydraulic tilt. It can be used for trailing when you tilt it all the way up the motor can rest on that lever.

Model # is ?-----Any pictures of the trim / tilt system on this motor ?

I’ll try to post a couple tonight.

Sorry for the delayed response. Was out of town for a bit. It's a model 70673. I'm having picture troubles at the moment.

This is the lever I was asking about.