You don't need to trash (And potentially weaken) your frame by drilling an access hole. I found a very easy way to fish the bolts in. Once the acces covers are off get a piece a stiff copper wire that is a little over one foot long. Bend a 'U' shape into one end with a pair of pliers so that it makes a 'U' about 1/2 inch in size and make the 'U' face forward on the wire (imagine a
Shuffle Board Stick but with a deepr 'U'). Then slip the shaft of the bolt to be fished into the 'U' and squeeze the arms of the 'U' slightly around the bolt to hold it firmly in place (So it won't come loose while fishing it down the frame). Then all you need to do is stick the stiff wire with the bolt on the end to where the bolt holes in the frame are. Once you thread the nut on a few spins just tug on the wire and the bolt will remain behind.
Its very easy and works very well...a coat hanger can also be used as the wire.
John
];')