It has been several years since I have worked with the MCP23008 and the Propeller, and looking back at past circuitry, it is really difficult to get a quick grasp on what I did in the past, due to some real crowded circuitry. Furthermore, I believe I tested this circuitry in the past, but I am not absolutely 100% certain.
From various drawings and schematics, it looks like I powered the MCP23008 with 3.3V and used 10K pullups on the SCL, SDA, and RESET pins going into the chip.
Additionally, for pushbuttons, it appears as though I used single 10K ohm pulldowns and for LEDs I used 100 ohm current limiters.
I believe this setup worked, because I had to have some means of testing my sd interface in the past, but as mentioned I am not certain.
Do this sound right and workable?