I only used one but used small relays to for the outputs since the TR7 current output is quite low. This was a little cheaper than getting two of them. Probably be a wiring headache for the novice.
If you get one of the older TR7, you might need to delay the output to the brake line as the 740BT needs to see the parking brake on before the foot brake released. Older TR7 dropped the signals simultaneously, failing to set the 740BT.