Hello,
yes did one years ago with Markits wheels, plenty of room as I recall with no nasty surprises.
Downside was it wouldn’t pull very much as I think the original early Hornby ones had traction tyres on one set of drivers. The slippery nature of the nickel silver for the tyres then being used by Markits didn’t help.
If I did one now, I would use the Gibson conversion wheels with mild steel tyres, should improve traction a bit, but you could weight the tender so it bears on the drag beam of the loco to help haulage.
Hope this is helpful!
Pete Hill