I've never heard or seen a drive like that (Well, not 5.25" anyway). Im afraid the only way foward I can see is to either trace the wires back, or try to find a different drive and do a similar mod.
EDIT: :-? I assume that you still want to be able to load/unload CDs from the drive once it’s been moved? Assuming that, you've got the perfect drive - If the button is on the front of the tray, im baffled as to why it needs to be elsewhere...
Eg, If the eject button is hidden = Hidden tray = Hidden (And unusable) drive...