3/32' v 1/8' ?

if you are getting a bigger freewheel you might as well get a new 1/8" chain (e.g. kmc z510hx), then it doesn't matter if you accidentally buy a 3/32" or 1/8" freewheel as all will work.

alternatively, if you are going up by one tooth, you could get a halflink.

i was thinking about going for this one :)

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=290361251993&ssPageName=STRK:MEWAX:IT