The Big Minneapolis...

Are these the same engine?

They are not the same engine. They are both 45 Hp Minneapolis engines but the top one is a 45 double tandem compound and the bottom one at the show is a 45 single tandem compound. If you look to the right hand side of the bottom picture you can see the cylinder. Compare that to the right hand side of the one you posted first. The only thing known to have survived from the one you posted above is the steam dome from the boiler. That one was owned by Jack Anderson near Fullerton ND. Nice comparison shot though.

A 45 double tandem compound does still exist but in poor condition. It may someday be returned to service.

Thanks Darren!