Bicycle Mechanics - Transforming downtube/stem shifters into thumb shifters?

I don't care for the 'black plastic' look of most thumb shifters that I've seen. I'm wondering how hard it would be to decompose a set of thumbshifters and a set of downtube or stem shifters, and then reassemble them such that I now had a set of all-metal thumbshifters that would agree visually with all-metal brake levers and clamps on a cruiser/stache bar.

Has anyone successfully done that? Alternatively, does anyone know of all-metal thumbshifters that would suit a 3x5 setup?

Don't know, but there's at least one other thread on this: http://www.bikeforums.net/showthread.php?t=101942, maybe there's an answer in there.

The thing you want is Paul's Thumbies (http://www.paulcomp.com/thumbmtn.html), made by Paul Components.

They won't mount down-tube shifters, but they use Shimano bar-end shifters (and possibly down-tube shifters; I don't remember if Shimano barcons have basically the same mounting design as dt shifters).
Here's the look:

http://www.paulcomp.com/thumbie.inside.jpg (http://www.paulcomp.com/thumbmtn.html)

Don't know, but there's at least one other thread on this: http://www.bikeforums.net/showthread.php?t=101942, maybe there's an answer in there.
Thanks. I don't know how I missed that :(

The thing you want is Paul's Thumbies (http://www.paulcomp.com/thumbmtn.html), made by Paul Components.
I looked at those, too. Apart from also looking "black plastic"-y, nearly $50 feels quite expensive. Do you know of anyone who's making something equivalent for cheaper?