What actuator do I pair with an EPG governor?

The 8290 EPG governor produces a control signal, not motion -- it needs an actuator to actually move the fuel linkage. The 8256-016 is the matching rotary actuator: 3.2 N·m of torque through a 42° stroke, powered straight from the 24 VDC control supply. The alternative, driving the rack with a pneumatic actuator, adds air supply, positioners, and a failure-mode question the electrically powered unit avoids.

Will it survive the engine bay?

The -40 to +93 °C range and cast-aluminum housing with corrosion-treated internals are built for the engine compartment, not a climate-controlled panel. Vibration and shock ratings follow MIL-STD-810C, so mounting it on a reciprocating engine or genset -- where a standard servo would fatigue -- is the job it was designed for.