I made a similar extra large bait board 10 years ago and fitted it to my 23’ Grady White - made from 18mm white food grade cutting board and incorporating a drain with a 50mm hose to take the blood away. I added an American 4 rod rack with knife slots at the back and various clips to hold fishing pliers etc, together with a 1m stainless ruler to check against size limits.
It is super strong and I can stand on it without it moving.
It has stood up to regular use and I recently transferred it to my Rodman that I shipped to New Zealand - using a couple of custom made stainless supports that fit into two existing rod holders to give a comfortable filleting height. The board needed a bit of a rub down after 10 years of UV and weather, but it now looks as good as new.
The red arrows on the ruler are 30cm for Snapper and 75cm for KIngfish - my two target species for the table - and size and bag limits are strictly enforced (and widely supported by most anglers)
Charlie was asking where to get the Board. I found a manufacturer near Luton via Google and they were very helpful, offering to do all the cutting as they said it was difficult with household DIY tools. This was a godsend, as the plastic welds itself as you cut………it took me two hours just to cut the hole for the drain plug, so much so that I abandoned the idea of fitting a drain in each rear corner.
I am now back in NZ enjoying the start of summer and the best of the fishing, so hopefully the bait/filleting board will be good for another ten years.
Ian