John,
First off... nice selection of vehicles. (see vehicles #1 & #3 in my signature).
A Nissan T-Diesel??? Very nice swap.
Regarding squirl cage removal:
Here's a link with good info:
http://www.serenitysys.com/MB/Service_Info/W124%20Blower%20Motor/index.htm
I also recall reading that it helps to cut the shafts on each side of the motor (with a dremel or hacksaw). That way you have easier/straight access to the cages. I believe this may aid in pressing the shaft out.
Jeff Pierce