That set is PLPR4, 72639 is PLPR4 itself and 977974 is TIC2, although its mainly a brake force and toilet coach at the moment as there is no equipment in use on it.
6263 is one of the MK1 Gen Vans and 9701 is a DBSO, these are interchangeable with any of the others in use
PLPR1 is at least...