O/D Push Button??

Hi, I did the 518 overdirve trans swap to my 73 duster, and I was just wondring if thier is anyway to wire up a push button swith out of a dodge van to work with it. I got the O/D swith out of a 94 dodge van a the junk yard, it's square, and lights up only when it's off. I know on the van it was wired to the computer, but is it possible to make it work with relays or somthing instead? Has anyone tried or have got one of these buttons to work? If so, could you please post a diagram of how to wire it up. Thanks in advace.

Mike