Cam expansion plug……1-7/8 or 1-13/16??

Hello, picked up my 340 block from the machine shop and he gave me the cam plug to install(they forgot to!….scary, I know!). He gave me a 1-13/16 concave disc type expansion plug, and it just seems to damn small! All the freeze plug type call for 1-7/8 but that is a diff type plug, but I feel the disc type peen in style should be 1-7/8 as well since this is so darn loose in the hole. Thoughts engine builders??