Exhaust Manifold Flange Size

[gable74]

He guys,
I bought some after market Rams Horn manifolds last year and just got around to installing them this weekend. They were pretty easy to install and everything went smooth. I am dropping the truck off at the exhaust shop Friday to get the tubes ran. I have some quiet Walker mufflers to hand over but I do not have the collector flanges that bolt to the manifolds. They looked like they were the ball type flanges. I am not an exhaust expert so I am trying to figure out if....

- There is a difference between the donut type and the ball type flanges?
- What size is the flange? 2.5"?
- Would a decent exhaust shop already have what they need to transition from
the manifold to the pipes?

I plan on calling them in a little bit to verify some of these questions but I wanted to see what you all had to say too.

Thanks,