Aluminum diamond plate on painted plywood

Finally got my diamond plate cut (mostly) and am ready to put it on and I'm getting cold feet. I know there's been a lot of discussion on best ways to attach aluminum to your entire td, but...I'm just putting pebble guard diamond plate along the bottom edge (about 9 inches on the sides, a foot or so on the front/back and hoping someone may have suggestions on the best way to attach...
My camper is painted plywood. I bought it mostly pre-built, so not entirely sure of the treatment done to said plywood, but it's holding up okay. I've read enough pros and cons about different methods of attaching a skin, but they seldom seem to address my specific case of just the bottom part on wood. These are just cut sections of diamond plate (16 gauge) by the way, no trim. (There's wood molding at the corners, so it butts up against those.)
Here's what I see as options for attaching... My worry of course is moisture--scared of it getting in, but more scared of it not getting out.
1. Stainless steels screws (with the holes siliconed, of course) every 6 inches or so around the edges. Nothing else. This wouldn't offer any protection from water getting in--but--it wouldn't hinder water getting out, either.
2. Screws WITH a line of caulk along the top inner edge and maybe the sides--preventing water from getting in from above, while not being a barrier for water getting out at the bottom.
3. Screws, and silicone around ALL inner edges. More waterproof, but will it trap moisture?
4. Screws and glue (like Liquid nails ). I've read a lot that this will breakdown over time, and not sure what it gives me over the screws. Also, won't be able to replace the plate without tearing up the plywood.
Or maybe some combination of the above (screws, glue and caulk at the edges? Is that overkill and a moisture trap?) Or something I'm not thinking of...
Here's a pic of one side ready to attach...
My camper is painted plywood. I bought it mostly pre-built, so not entirely sure of the treatment done to said plywood, but it's holding up okay. I've read enough pros and cons about different methods of attaching a skin, but they seldom seem to address my specific case of just the bottom part on wood. These are just cut sections of diamond plate (16 gauge) by the way, no trim. (There's wood molding at the corners, so it butts up against those.)
Here's what I see as options for attaching... My worry of course is moisture--scared of it getting in, but more scared of it not getting out.
1. Stainless steels screws (with the holes siliconed, of course) every 6 inches or so around the edges. Nothing else. This wouldn't offer any protection from water getting in--but--it wouldn't hinder water getting out, either.
2. Screws WITH a line of caulk along the top inner edge and maybe the sides--preventing water from getting in from above, while not being a barrier for water getting out at the bottom.
3. Screws, and silicone around ALL inner edges. More waterproof, but will it trap moisture?
4. Screws and glue (like Liquid nails ). I've read a lot that this will breakdown over time, and not sure what it gives me over the screws. Also, won't be able to replace the plate without tearing up the plywood.
Or maybe some combination of the above (screws, glue and caulk at the edges? Is that overkill and a moisture trap?) Or something I'm not thinking of...
Here's a pic of one side ready to attach...