No problem
Yes indeed, if you work on the basis that a bulk standard battalion of French or British line infantry around 600 men strong are an average FS of 7 or occasionally 8, then you would see a British Guard battalion of about 900-1000 men weighing in with an FS of about 13 or 14 and militia units and many Spanish at around an FS of 5.
Most line artillery are rated as 7, and the cavalry are similarly rated and structured around a couple of squadrons at about 300 men, so you should be able to use the FS as a guide for GdA in terms of their quality.
The letter refers to the skirmish capability or class of the unit with A best to D worst, ie no skirmish capability to talk of. Most French/British line battalions would start as B representing their attached light companies specifically trained to do the job.
You will see that I have followed what seems likely to be doctrine, certainly for the British and most likely for the French, in forming regimental/brigade light and voltiguer battalions of about 300 men and thus the battalions that have contributed their light companies to those battalions have had their individual skirmish capability downgraded to C to allow for lesser trained grenadiers doing the job at a battalion level if they find themselves unprotected by their own light battalion.
Certain British light battalions may well have 'R' against their skirmish class indicating that they have a group of riflemen among their unit.
Most Voltigeur and Light Bob battalions are rated B, with a quality unit such as the 95th Rifles of 43rd Light Infantry most likely rating an A.
goes to sea with the Terrain Mat.
