trunk floor prep--inside frame rails

[Brian in GA]

Okay, guys, need a little help and a pic or two on this.  I've got a 68 with a rusted out rear.  Have taken out the remains of the trunk floor and done all the clean-up and prep.  Had to do a some patching on the tabs on the rear frame rails, and am in the process of getting ready to put in the new two piece trunk floor.  Question is, I know there are two nuts welded to the inside of the frame rail (one on each side) to attach the rear cross-member.  I've completed that part.  But on inspection, there appears to be a place where another nut is supposed to go, and I don't know what it holds up?  My fear is, I'll put in the new floor and later find out I need a secured nut on the inside of the rail to attach something else from underneath, and I won't have access to install one at that point.  What do I need to know here? 

Thanks!

[fy469rtse]

Brian, if you can find your exhaust tip mounts, one for each side ,
Big steel plate with three bolt hole, pressed tab near where exhaust tip hanger mounts
two bolts go into welded nuts in bottom of rail, that exhaust hanger mount also doubles as the bottom bolt on your rear bumper over riders,
Check some off the build threads on here , I remember seeing lots of good photos for these areas, good to fix these now as will be a pain later ,

[Brian in GA]

That's exactly what I needed to know.  Lot of stuff missing off the back so I didn't have a reference. 

I was afraid of getting the trunk floor welded in, and later realizing I need to get inside the frame rail to bolt something up.