So.....
I see the picture of the "wasn't much help" impact. I see a picture of a normal breaker bar. Where's the "I'm not asking" breaker bar?
My "not asking bar" is a 1/2 drive bar with a 4-5' cheater pipe or floor jack handle slipped over it. Or if it's big enough a 1" drive ratchet with a similar pipe. Usually when those come out we're past removing a bolt and just trying to get the bolt head off to remove the piece. The 1/2 bar with cheater pipe did get used on some exhaust stuff recently.
Any how, good work on getting the bed off! Look forward to seeing pictures of the end results with the herculiner. That said, if you get it on your hootus.. Please, Please don't post pics, as this is a family friendly forum. However, please do share the details so we can have a good laugh at your expense.
(PS: If you are not familiar with the "Herculined Hootus" story, give it a search. I believe that it originated on Explorer Forums. It's a good cautionary tale for anyone using Herculiner and a great laugh.)
(PPS: Here's I found the original thread for reference:
https://www.explorerforum.com/forums/threads/how-do-i-get-herculiner-off-of-my-hootus.18595/)