Hi Charles,
I have a few classics myself Triumph and MG and usually the club scene provides the best knowledge of marque specialists as I am sure you know.
I have seen a few Allards race but not really taken much notice so had a google about. They were built mainly from Ford bits not sure if UK or American with regard to the brakes and as such should be fairly simple hydraulic.
Check the drum is true on a lathe.
Linings fitted correctly especially if they have leading and trailing shoes.
Hydraulics working and sound including Master and slaves.
Adjust till brake binds, press brakes on to ensure shoes are central and recheck.
Just slack off till drums turn freely.
Its an awful lot of power to rely on drums, in one of the articles I read it said that Jaguar had the upper hand on tight racing circuits due to better disc brakes.
Sydney seemed to want to fund his racing by making cars sounds quite a character.
Link to article that you may have seen.
Good old school garages and people are hard to find now a days as most technicians just swap bits and don't repair for cost reasons I guess.
Good luck with the brakes.
Don
http://www.allardj2x.com/pdf/short-history.pdf
