matt.smalley posted an openssl command that could be used to create the
p12 file at
https://jamfnation.jamfsoftware.com/discussion.html?id=16640. If that
works for you, you could avoid generating another CSR.
Does Step 3 in the KB for GSX help?
https://jamfnation.jamfsoftware.com/article.html?id=26 It looks like for
a CSR that is not generated in the JSS for GSX, directions for
generating the the key-pair are shown in Step 3