Usually CVs go on pretty easy.  Are you sure you got the right ones?  I have
done a bunch of these and never have to press them on to the shaft.
Something to look at before you put the whole shebang back together is the
round plates that are inside of the CV drive flanges on the tranny.  I took a
CV axle off of a customer's van one time (a non-running van that he was
parting out) and the boot was full of gear oil.  When I finally got it off,
the metal disk in the center of the CV flange came out along with all the oil
draining from the tranny.  Apprently this disk (I don't know the proper name
for it) had come loose at some point and had allowed transmission oil to leak
into the boot.  When you said that one side had an egg nog like substance in
it, it reminded me of this occasion.  Make sure those disks are in tight
before you put the new axle assemblies back on.  If not you may be
experiencing some leakage.  Might be that's why you were having the shifting
problem (low tranny oil level).
Just an idea.
Ken Wilford
Van-Again
John 3:16