If you order lifters from a Nissan dealer they will have two different parts queries as well. I think many '89-'90 production cars had the 'non-rebuildable' style with the press-fit ring (don't quote me on that though). I know my original engine in my car did, and I had to use some different lifters in order to rebuild them.
Really was a mystery for awhile personally as I was wondering why the heck my lifters wouldn't dis-assemble as per the rebuild guide! Hah
__________ Version 3.02 - Driven like it's supposed to be!