Re-Bedding Ports . . . Need Advice

[fmja10]

Greetings all....newby member here.

I'm removing and re-bedding at least two port windows on our 2004 Grand Banks 46CL. She came equipped with the Manship rectangular port windows from the factory. Units are angled and screw in from the inside. There's a plastic (???) trim ring on the outside.

Any tips/suggestions would be appreciated.

Thanks much in advance.