II
If i recall correctly, the 1S1 in DF was in fact a "1S1 - modified" and the C MGB (as fitted to BYDF) was also different to the A. I'm pretty sure that you had more power available to you if you went single-engine in "DF" than you would have had in a standard A++, although it has been a while and i've not flown a standard A++ so i could be wrong about this.
Definitely remember the unique torque gauges Dave B refers to - Used to keep a spare one on the shelf as it would have taken weeks to get another one made if one went U/S.
A nice machine indeed!
