sorry didnt read that very well. most trim is riveted on the newer boxes, cant help you on that one.
here is a parts list off of the kr557b model
557AK1400ATR 3 Drawer, Shallow
– 8-1257 6 Offset Runner, Std. Duty (Drs. 1,2)
– 8-1658 6 Channel Track, False Side (Drawers 1-3)
4-6 557AK15A 3 Drawer Assembly
7 557BK2500ATR 1 Drawer, Deep
– 8-267 8 Offset Runner HD (Dr. 6)
– 557K3700A 1 Lock Rod Assembly
– 558K6303 1 Trim Channel (Right) discontinued so be careful
– 8-7739 2 Caster, 5" Swivel w/Brake
– 8-7639 2 Caster, 5" Rigid
– 557K9010A 1 Caster Mounting Hardware Package
– 1-467 1 Spring (Locking Mechanism)
– 8-4937-1 1 Cam (Lock)
– 791X5000 1 Hardware Package
– KN450ASV 1 Nameplate