Help with cleaning a very dirty laser

I am trying to clean a laser that was left out for many years without any covers. I thoroughly cleaned it using soapy water and elbow grease and attached are photos of its current state.
There are still many dirty marks, and a layer of dirt seems almost baked into the surface. There are scuffy dirty marks on the gunnels as well as many stains on the underneath of the boat.

I seek guidance on cleaning it.

I have seen Soft Scrub recommended. Is it good? I live in the UK, is there a UK...

Help with cleaning a very dirty laser