I take it you have no handbook? Above is a link to the earliest Swift Group handbook available on-line (Swift made Abbey). Unfortunately they only go back 10 years, but some bits may be relevant.
If you go to the SwiftTalk forum, you may get some advice and you can ask about the older handbooks.
Amazing family weekend with old steam engines, classic car displays, market stalls, and full catering and bar. And camping on site - Save £25 by booking in advance.