No, I didn't take any of the wagons specifically but I may have a pic where they can be seen coupled the the Fowler's successor - a Mercedes Unimog that was fitted for road/rail. IIRC they were hoppers of about 20 tons capacity and painted mid blue in colour. I think they were very old and possibly ex-LNER. Whatever they were I'm fairly certain that they weren't the more usual 21-ton hoppers.
Regarding that 48DS; I believe it was "preserved" but that term seems to mean almost anything these days and I'm not at all sure where. You see I when I stopped chasing these things I also stopped updating my IRS books. I think it went to some scheme or other that hoped to re-open an old line in the north of England, but not a major "heritage" railway.
Sorry I can't be of any more help.
The hoppers at BOCM Selby were Charles Roberts 20 ton Hoppers; at least one could be identified as a former 'Bedford Electricity Authority' wagon.