Paul,
 It looks like Jon from Pico contacted you. He works alot with EMC and
has a nice setup. Go to http://www.usdigital.com/products/e5/  look over
these to see if this may fit the bill, 500 count differental encoder.
This will replace the resolver. Another direct hookup is
www.camsoft.com, a little more pricey. I know you do not like Windows,
but the other option is www.artofcnc.ca  . You might check with the guys
on http://groups.yahoo.com/group/CAD_CAM_EDM_DRO/ to see if there is
anyone close to you, this is the EMC group.
Richard