Soldier Series + Street Fighter II Question

Hi Listers,
    I was wondering what were the first five games in the Soldier
Series? The cover of Super Star Soldier has a 6 printed on it, Final
Soldier with a Roman numeral 7, and Soldier Blade with an 8, so I'm
assuming there were others before it.
    The other question is, what part of the game in SF II does Track 20
(BGM) play?

Thanks,
EL