Need help combining/modifying existing filters

For his 8th grade history day project, my 13-year old son is making a model of the Turtle submersible. Here is a photo of a replica of the vehicle:

http://en.wikipedia.org/wiki/File:Tur...museum.jpg

He is doing this project in OpenSim using simonastick.com and will be piloting the vehicle and making a video of it. He has the scripts for making it work and has the design mostly done, but doesn't have the correct textures for it. I told him I would help with that, but can't find exactly the right wood using FF. (I have 3.0 Professional.)

What I need to figure out how to do is modify this filter to show only one set of nails:

http://www.filterforge.com/filters/1321.html

Then combine it with this to create a lacquered effect:

http://www.filterforge.com/filters/7672.html

I have done one or two of the easiest tutorials, but this is way above my abilities using the editor. It would be great if a kindly expert could give me some tips doing this or, perhaps, if the project interests you, make this and upload it and you would have one very grateful mother here!

I couldn't find the metal textures in available filters, but I think I can find most of what I need at http://www.cgtextures.com/

That looks great! Thank you so much for the help. Seeing it as XML it makes a lot more sense to me than the visual editor. So now I need to figure out how to make it seamless again and to add the lacquered effect.