I am not familiar with the SCXI-1129, but I have used IDC type connectors for similar types of cards (mainly SCXI 1163). Most of NI's switch hardware has standard spaced pins, so look for an Insulation Displacement Connector (IDC) that has the right number of pins, or one that can be cut to fit over the pins.
We made a big box with all the loads and connection points, so the SCXI card only has the wires running to it that you need. Then run 22 gauge bundled wire from the connector box to the card, and crimp the wire into the IDC connector.