>I need to run FPDOS on Windows Server 2012 R2 64-bit. I understand DOSBox should help with this.
>
>I haven't used it before but ISTR you have (?) If so can you offer any pointers for settings that would work well for FPDOS?

Dragan claims DosBox runs good but I faced some difficulities some weird things. Use Oracle VM (it's free) and find a XP or 98 license or download FreeDos.