Trim and tilt on 200 Vindicator

1998 Evinrude Vindicator 200 HP.
Model # E200STLECE
Ser. # G 04461856

New problem on the trim and tilt system.

I can tilt the motor to the full 'up' position and it will stay there for as long as I leave it there.

I can lower it to within an inch or so of the trim rams and it will no longer hold.
It closes very slowly against the trim rams (15 minutes or so) then will continue to drop until the trim rams are fully closed.

There are no signs of a fluid leak anywhere externally. Fluid level is correct.
Also, the overpaint from the factory has not been disturbed so I don't think it's ever been worked on.

My guess is that the rams need to be rebuilt. Yes/no??
If they do, does this have to be done at a shop or can I do this myself. I generally do most all of my own outboard motor repairs but, I've never had to tackle a trim and tilt unit.
I'd appreciate any input.
Thanks.
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