Very good catch.
https://www.gladdingmcbean.com/sites/default/files/attachments/PipeBrochure_0.pdf
6” dia pipe has an OD of 7-7/8” and the bell end has an OD of 10-7/16”
I suspect those are industry-wide standards.
Based on that chart, the profile of the vcp actually stood
over 9 inches tall, suspended up on the bell.