On page 59 Figure 4-3 is Showing Figure C (Bottom Left) it is showing that “Not a Bumper” and “Not Ok” are not correct… So for “Not Ok” is showing that you do not need to have the bumper that long, Then for “Not a Bumper” you do not need to have the Bumper in the inside of the robot.
Am I understanding this correctly? 
I do understand that you will need to cover all of the corners of the frame. Also I remember that other years they had bumpers but I do not know what the rules were for that.
First off, rules from previous years don’t apply. Only the one in the 2016 FIRST Stronghold manual apply.
The “Not okay” pointing to the bumper is because that bumper is less than 8", therefore not adequate cover for the corner of the side.
You are correct about not needing bumpers inside of your frame perimeter, only at least 8" of exterior corners.
Well… sort of.
Not a Bumper: There is nothing saying that you can’t have a structure in there that is built like a Bumper. However, you cannot count it as a Bumper. It won’t count towards the 8". The reason is that it’s not on the Frame Perimeter.
Not OK (bottom): There isn’t a bumper there, and there needs to be 8" of bumper because it’s next to a corner of the Frame Perimeter.
Not OK (right): It’s “Not OK” because the bumper is too short (< 8"), and the frame it’s mounted to is too short for a full bumper, but the Frame Perimeter is clearly longer than 8".
Bear in mind I’m looking at the most recent version of that image, which was in today’s Team Update.
Correct?
That looks like the right image. So the “Not OK” flags are for no bumper where there should be one and a bumper that is too short (and on a frame section that is too short to support a full 8"+ bumper).
Not a bumper also means that it is part of the robot for the purposes of weight, costing, bag & tag rules, and so on.
This may be a stupid question, but…
We don’t have to bag and tag the bumpers, right? Do they count towards your withholding allowance??
Thanks!
Nope! They were redefined fairly recently (2014?) to not be part of the robot, and therefore not subject to the various robot building rules.
BUMPER a protective assembly designed to attach to the exterior of the ROBOT and
constructed as specified in Section 4 (4.7 BUMPER Rules)
Bumpers are excluded from both.