Earlier, Sean Trost wrote

...and an aircraft sump...

I disagree. The downdraft carb behind the accessory case is one of the
hallmarks of the O-290G, so I believe that it still has the GPU sump.
Also, the heavy crankcase flange at the crank output is another O-290G
giveaway.

It _does_ look like it has two mags, and that's a puzzler to me.

Thanks, and best regards to all

Bob K.
http://www.hpaircraft.com/hp-24