First, congratulations on dodging that bullet. Retrieving the speedo gear as you did is not easy.
As for the backup switch, of course there is one, or in your case, there - should - be one.
For more photos, see this at Mike Dailey's Panteraplace website:
http://www.panteraplace.com/page230.htm
You should know the switch can be installed too far into the selector cover resulting in a mechanical lock-out of selecting reverse. Adjust its depth into the cover with shim washers on the outside threads.
Larry
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