At this point I'm really considering swapping my speedo out for an electronic one and runnning a wire conduit in place of the cable. I can get the sensor (Toyota part too) to put on my tcase. I just gotta get the speedo itself and find out how to wire the Toyota connector up to it. Honestly I think the GPS setup is a great idea, but you're still susceptible to loss of signal if it's heavily overcast, you're driving in the mountains, or under alot of cover from foliage.
are you really whinging about this? "oh no my gps lost signal for two fxxxing minutes and i dont know how fast im going.....im such a pussy..."
grow a sack dude