Wondering if Chlorion aerarium could be a possibility. It can be found in Montana. The other thing that gets me is there is an almost gold looking color just underneath the base of the wings. Can be seen on all the photos I took. Can't find any wasp photos that show this.

The texture of the thorax and head is not very smooth. I think that we can rule them out. The goldish glint could be anything from a speck of dirt to a strong reflection of the sunlight coming through the wings. It's hard to say for sure.

Cool, Would really love to know for sure though. I have been submitting observations and photos to the Montana State Field Guide website and they have been very excited about me helping them provide them with photos of insects which they have very few photos of if any. Don't want to send them anything I am not confident about. I have provided them with a couple of insecst they didn't have in their field guide. Would love to send them another one.