Not sure if I'm posting this in the right place.

My convertible top motor started leaking about 10 years ago. I took it to a local rebuilder and they replaced some seals inside. It seemed to still slowly seep so they did it again and then things seemed ok...

I recently removed the rear seat to find that the slow seeping has continued and left a sheen of fluid on the sheet metal behind the rear seat back and kind of made a mess at the base.

I don't think it's an inside seal, though because it seems to have fluid building up around the middle of the motor -- where the reservoir meets the motor body. There looks to be a large o-ring that seals the two pieces together. At the end of the reservoir is a large, weird, 3-sided screw head.

Is this the head of a large screw that runs the length of the reservoir and screws into the motor body to squeeze and seal the two pieces together against the o-ring? Has anyone taken one of these apart and can shed some light on how this thing works? Don't want to screw mine up trying to tighten the wrong thing.