jdownzarzap1,
I tested this out with a 6031e and found that AI 45 is pin 54 and AI 46 is pin 53. This is the same as is indicated in the most recent E Series User Manual (http://digital.ni.com/manuals.nsf/websearch/4449EE33A429639786256E31005A324B?OpenDocument&node=132100_US).
Ames
Applications Engineering
National Instruments