From my modeling notes the salida wreck train consisted of
Derrick OP and service flat 06063
Rail and Tie car 06051
Wheel and tie car 06092
Rail and tie car 06084
Box 04426 Cable car
Box 04444 Block car
Box 04549 Tool car
X66 (former long RPO)
There might have been more support or living quarters cars that were either attached or casually dispatched with the wreck train but I have not gathered any more info.
The ties, rail and wheels were used to build shoofly tracks down hills or embankments to recover equipment that went off the ROW. The wheels were spares for immediate replacement during wrecking recovery. To my knowledge the car was not used on its own to transport wheels.