OEM Muffler Replacement Clamps/Connectors

Hi. I'm new to the forum. I have a 2003 Tacoma 2.7L SR5. My muffler needs replaced (big hole) and I want to change it myself. I have ordered a new Walker muffler that has the entire tail pipe out the back and a little stub pipe out the front. I want to use a connector and clamps to attach the new muffler to the OEM pipe. I am unsure of what size connector and clamps to use. I know the OEM pipe is 2.25" from what I have read online but it isn't clear if that is ID or OD. (I'm assuming ID) I saw a video where someone put a 2.125ID pipe inside the OEM pipe and clamped that. Do I want to use a smaller connector inside or larger connector outside? What size connectors and clamps do I need? Thanks.

 

I bought a few of both sizes (super cheap on Rock auto). I think I used both sizes, as you end up telescoping pipe to make everything work. In the end I still welded to the muffler as I had a small leak with the clamp. Good news is most local auto parts places carry clamps and short amounts of pipe.