Just to clear up any confusion if there is any.... the bypass information is posted on my web site here:
http://www.sminntech.com/z1flash.html
June 06 and before:
Leave parking brake wire floating, do not connect it to anything and manually flash your lights (or put in my circuit to do it for you).
July 06 and after:
Ground the parking brake wire and the other wire (as shown on the web site above). No circuit or flashing needed.
Note, the cut off time is not absolutely defined yet, these dates are approximate. Some have said that they have a June 06 that flashing does not work and some have said they have a July 06 where flashing did work. The cut off is around the June/July cross over but there might be one or two units in the month that respond to a bypass from the other month. May and before are all flashers and August and after is assumed to be all 2 wire grounds.