Here's what I came up with today going through Alldata and some other sources. It's a start at least.
Year Fed/CA Cab Trans Body Part #
1998
ALL STD ? 4X4 89661-04372
ALL EXT/DBL M 4X4 89661-04412
EXT/DBL A 4X4 89661-04540
ALL STD ? 4X4 89661-04372
EXT/DBL M 4X4 89661-04412
EXT/DBL A 4X4 89661-04540
1999 ALL STD ? 4X4 89661-04392
ALL EXT/DBL M 4X4 89661-04451
ALL EXT/DBL A 4X4 89661-04461
ALL EXT/DBL M PRE 89661-04431
ALL EXT/DBL A PRE 89661-04441
ALL STD ? 4X4 89661-04392
ALL EXT/DBL M 4X4 89661-04451
EXT/DBL A 4X4 89661-04461
2000 FED STD M 4X4 89661-04580
CA STD M 4X4 89661-04631
FED EXT/DBL M 4X4 89661-04570
CA EXT/DBL M 4X4 89661-04621
FED A 4X4 89661-04701
CA A 4X4 89661-04680
ALL EXT/DBL M PRE 89661-04650
ALL A(COLUMN) PRE 89661-04660
FED A (FLOOR) PRE 89661-04701
CA A (FLOOR) PRE 89661-04680
ALL EXT/DBL M 2WD 89661-04650
ALL EXT/DBL A (COLUMN) 2WD 89661-04660
FED EXT/DBL A (FLOOR) 2WD 89661-04701
CA EXT/DBL A (FLOOR) 2WD 89661-04680
Well that worked out like crap, but you get the idea. most of the numbers ending in "0" have been superseeded to "1", so either will work. The toyota reman units were assigned an "84" on the end of the part numbers