I dig it. Looks great.
What is this tank trim you speak of?
It's that same sort of thing you have on some old style helmets going around the edge; made of black rubber.
Some older bikes used to have it on the welded tank edge to finish it off nicely.
I found it on eBay, 4 metres or so of the stuff
I'll put up a pic of it when I'm done; haven't received it yet, should be here this week.