not sure, i seen a project once someone used WOOD filler.. although bondo will probably work better especially since its NOT wood..
anyway they put a new sheet of metal under it, filled in the holes, sanded it, then drilled the holes and put a overlay on it.
im not sure what they used to drill the holes.. that would have to be a pretty meaty twist bit.
im curious as well i have a centipede i was thinking of using but it also has a metal CP..
i had thought of trying to replace the top with a section of wood.. or recreate the whole pannel in wood, but have'nt looked seriously at it.
ps i dont know if i previously mentioned this i have a pair of those sticks as well and they are the sux, extremely short throw, weak centering, if for some reason you dont like the feel.. dont toss them the shafts also fit a happ/Il competition base and probably others, although not the supers they seem to use a larger shaft.