Since it was probably custom made for the Contender and not a generic size, i would think that the brackets lined up with the edge of the console, both of which, would be screwed directly into the stringers.
As for the rear brackets they could be to mount another foot rest pipe on, for more rod holders. ALso on Contenders website this is an option for seating for the 30 Tournament, "Tournament leaning post (Features
tray, cooler base, (4) rod holders and folding footrest)" This is right off Condender's website.
The holes in the floor?
I will let someone else chime in on that one.
As far as the toggle bolts i have not used them on my boats. But i have used them for mounting shelving, tv brackets, etc in restaurants, bars etc,. IMO they are as strong as an equivalent size bolt and nut with a fender washer. We always put 1/2 or 3/4 plywood on the studs before sheetrock to anchor stuff to. Its strong. One builing owner didn't like the idea. I told him if he could rip the shelving down i will replace it with his choice of fasteners on
MY time and dime. After a couple tries he gave up.
