I’m working on a project (yeah, big surprise there) that would do well with a set of the 6mm pillow blocks to support some axle shafts. I see the measurements for mounting hole diameter, hole spacing, and a base-to-center measurement, but I need to know the width of the block along its short dimension. Based on the plain 6mm bearing’s thickness (4mm), and the photos of the pillow block on its product page, I’m guesstimating that it’s somewhere in the 6mm to 8mm range?
This is one of those red headed step child parts. lol I planned to make SAE bearing sizes but never got around to it. So, it’s an SAE part with a metric bearing. 
The part is 0.25" wide.