Wow - I'm not sure it can be simplified. BN1 & BN2's were a confusing mix of wrench & thread sizes.
For example, a 7/16" bolt shank can have several thread pitches & bolt head sizes.
A 7/16 bolt can have 18 tpi - BSF, 14 tpi - BSW, or 20 tpi - UNF. This same bolt can require a 7/16W, 1/2BSF, 5/8UNF, or 11/16 wrench.
There are exceptions everywhere. For example the standard head studs are 7/16-18BSF on both ends, but have a nut which requires a 3/8W wrench instead of the more common 7/16W. The new high tensile head studs are 7/16-18BSF on the block end & 7/16-20 UNF on the nut end, & require an 11/16 wrench.
There are quite a few non standard bolt threads & head sizes throughout the car.
As Bundy said:
"The pitch of the thread doesn't come close to the Whitworth. Once again BSF is a Whitworth thread form. It has a 55 degree thread angle whereas the "unified" thread form has 60 Degree thread angle."
-- Don't mix 55 degree & 60 degree thread forms.
My best advice is to never force a tap or die or nut if it doesn't want to go easily.
Get BSF, & UNF taps. Get BSW taps only if you determine one is really needed. Get dies only if desperate, see below.
You will also need some Whitworth wrenches.
If in doubt, get new hardware from Moss that matches the exact application. Even if you are only getting two or three at a time. A few new bolts or studs can be much cheaper than buying the required dies.
D