Won’t start

Actually don't know that one.

1850 is a very common carb. We'll have no problem helping on that.
Not sure this is on track to helping with your problem. I think you posted that fuel did come out of the shooters. yes?

Side hung floats. Floats go parallel when the bowl is held upside down.
That's generally a good rule of thumb with Holley side hungs
https://documents.holley.com/199r8339.pdf

https://documents.holley.com/199r8179-1rev.pdf
The second link is the document I got with my rebuilt kit and couldn’t find a number that matched anything on my carb. I am going to remove the bowls and try setting them inverted like the first link suggests.