If you are simply connecting to 3.3v devices on the 059 kit I/O pins, you can configure the connected outputs on the PSOC to be open collector, pulled up with resistors connected to your 3.3v supply. Configure the inputs to be high impedance, and the 3.3v devices will drive the input levels high enough to be recognized by the PSOC 5 running at 5v. Using resistors may limit the digital speeds involved, but I've use 115,200 baud rates with no problems communicating device to device a 3.3v into a 5v input.
