your '98 transfer case will bolt to the 92 Ax-15, I did a late model conversion on my '92 with AX-15, I have a '98 231 bolted to the '92 AX-15 with no issues. other than I have not be able to locate a 5 speed boot for the '98 console yet.
Iv got a complete front grill/ header panel assembly, grey visors and tilt steering column/ wheel with cruise and wipers. ill be headed toward balt. md in a few weeks
-Kurt