WR Intercity Mk2 coaches

[125_driver]

Having flicked through a couple of platform 5 books, it seems there where a couple of mk2 coaches allocated to Old Oak Common, allocated to the intercity XC pool during 1990 - 1991. Now I know Old Oak had plenty of Great Western mk2s on allocation until 1991, but wasn't aware of any allocated to XC? The coaches in question are 13602 and 13583. I have attempted to Google them for pictures without luck, can anyone help with pictures of these coaches and or any details as to why Old Oak had XC coaches allocated to it until 1991? Thanks.