Lee, a picture of your setup would be helpful.
These boats came from the factory with access panel for the battery and trim motor. The access panels were covered with carpet that attached to the bulkhead with snap fasteners.
You can get snap fasteners and snap buttons online and make your own cover.
You can also find the engine cowling latches online. Check your setup and see what you have and match the latch points. Pictures of your cowling latch connections would be helpful also.
I had a similar engine cowling on my first boat. I used 1.5 inch heavy canvas webbing with snap fasteners on each end to hold my cowling down.
2006 Bayliner BR205
A1 Gen 2 1.47
5.0 carb engine