5.0 .. its a solid piece in the middle. I haven't looked at it to hard but it seems it may be a separate piece than the ones on the side. I'd like to maybe cut out for the bar but I don't want to jack it all up. Lol. There's not really any places around where I live that does stuff like that. Maybe almost 3 hours away but not local so I'm on my own when trying to do these things

 

I am pretty sure that filler pops out if its there. If you follow step 1 and 2 from this video, you should be able to visualize the back of that space and pop out the filler piece.
I think the most challenging part is fabricating a bracket.

 

Yeah I believe whats gonna be bad for me is being able to get to it and test fitting to try and make some kind of bracket. I sure wish I had some kind of shop to do this for me. Lol