A Bulldog stabiliser will be in 3 parts which are the base plate that is bolted behind the towball fixed flange, the leaf spring main body and the nylon bracket in which the blade slides in to which is drilled and bolted to the caravan's 'A' frame. However, a 1992 caravan most likely has a chassis manufactured by AL-KO in which case they advise not to drill any holes in any part of the chassis merely because of weakening the structure.
Take note of their comments in the link below.