Shows 108. (don't know where that 124 is from, as I don't see it anywhere?)
For AWS I would probably use something like 8x HD C and 112x HD Y. Since the routes flown by that type usually are not so long that having STD seat would not bring in any very meaningful advantage.
And yes, using STD seats will give you a 104 total in the game like you said, but it is purely impossible to start adjusting the seat configurations for every model individually to match the manufacturer's suggested configs (will not happen ever as it would be a logistical nightmare. There are about 500 planes in the database....). Each seat type in AWS have certain dimensions and the system calculates the config based on the a/c size and dimensions+number of seats selected, and in most of the cases it is not the same as the manufacturer's config, since the seat size and pitch is different in every a/c.