Super duty rivet removal?

I know how most rivets work, but these on my old boat just look SOLID. I want to remove the flooring and redo the layout. To remove the floor, I'm pretty sure I have to remove the console/livewell/storage to get this done. The console is attached to the wall with 12-13 rivets on the side of the boat. It is just screwed to the decking on the bottom.



These are samples of what they look like. These are remnants from a brace that one of the prior owners removed but just cutting the metal - I'll be redoing the brace as part of my renovation. Do I have to grind these rivets off (from the inside) to get them out? Doesn't seem like a drill would work that well.

Here's the boat itself. As you can see, there is not a 'seat' for anyone but the driver. I'll be moving the livewell to the middle of the front deck - extending the back deck to the driver's seat and installing a passenger seat (and jumpseats for the kids)- buiding storage into the front deck - recarpeting - and numerous other little touches. That's the plan anyway.



Thanks,
Will

Those and most rivets on a hull are buck rivets. The side in the pic is the side that gets flattened during the bucking process. You can just drill them out. I've drilled and rebucked 1000's of rivets on 18 wheeler trailers and did many on my buddies boat.

To replace with the new ones, you'll need an airhammer buck rivet and a block of steel.

Get a flap disk on a 4.5 inch angle grinder, and grind the rivet flush with the parent metal. Then, take a hammer and punch, and knock the rivet free.