Master bed size

[Keilai]

I have a 2018 28BHBE the bed is 60" wide but there is a 65" spot for it. There is only 60 inches of plywood and then some really flimsy board that is stapled to fill the rest of the space, first why in the hell is there a five inch gap? Should I get a wider matress if I replace the stock one? Also what are the little flimsy wood pieces for?

[o2silverado]

The flimsy pieces of wood are just filler. 60" is standard queen width. You need at least 74" to fit a king size .