Maria Oldal of The Morgan had requested to see $a and $2 combinations for the 655 field, so I was able to generate that and place a link on the page for that field: <http://experimental.worldcat.org/marcusage/655.html>. Although I will be somewhat limited as to the number of ad hoc reports like this I can generate, go ahead and request anything you want to see and I will see if I can get to it. Thanks,
Roy