Suggestions

[Victor]

Not for the boat really, but this is where the expertise is. I'm installing a bathroom partition and laying down "flooring" using 4/8 wood-backed vinyl sheets, not because I'm cheap (although I am) but because I want to be able to remove them if desired. Question is, is there some way to fasten them down with removable fasteners (like screws) that won't show?

[maa. melee]

Im not exactly sure how well the vinyl is glued to the lumber but you might be able to get away with the hidden faster technique used for wallpaper and under-fastenings. Basically what you do is cut a small 'V' in the vinyl with a sharp knife or what I find works well too is a right-angle chisel. The peel back from the tip of the V, drive your fastener and then glue the vinyl back down.

[JimConlin]

There are some metal clips which are used to secure dech (porch not boat) planks from beneath. No fastenings show on top.

[Stiletto]

If they have a tongue and groove edge they can probably be secret nailed by drilling and skewing through the tongue.