I have a client that wants to do a 14 week time lapse of Orchids growing and was wondering if anyone has come up with a firmware hack for the Go Pro to increase the time between shots to even 1 every 60 minutes instead of 1 every 60 seconds

No there is currently a FW fault preventing one button mode to be used as an interval for stills.
This huge thread explains a lot of things. GoProUser.freeforums.org • View topic - the GoPro Hero HD "bus" interface (http://goprouser.freeforums.org/post13977.html#p13977)

Your best bet is to rig up mechanical actuation of the power and shutter buttons or hard wire to the buttons and connect delay timers.

The Gopro will not perform well powered on indefinitely, so you also need a power up delay.