Welcome to the forum.
Are you a Mk1 (sterndrive) or Mk2 (jet). If it's the latter, you can ignore most of the following.
I've attached some pic's of what mine looked like which was pretty standard / original with the exception of the stainless hoop. Of all the hundreds of pic's I've taken, there wasn't really any good ones of the engine cover.
The seat covers were held in place by press studs on the edges and velcro strips on the top.
The additional holes may be for the viewing port and / or the hole through which you poked the fire extiguisher.
I've still got the engine side panels, tops, cushions, console and several covers - engine, console and overall cover. They were made by the chap who makes them for the MoD who was also the previous owner of the boat. I've changed the arrangement so they are surplus to requirements.
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