Rusted out rear sill

[hollowbase]

You can guess my problem from title. Mine is 4/75 and it appears the sill at CCOT is pretty good, so that's the way I'm planning on going. I do have questions though in my attempt to understand what I'm getting into. My understanding is that the sill is welded to the bed and also bolted to the frame. Is there also welds at the quarter panels? Also from looking at threads here the sill cover is also welded to the bed and spot welded to the sill and welded to the corners of the quarter panels, is that correct?

 

[brian]

Correct

 

[Living in the Past]

The rear floor is sandwiched between the rear sill and sill cover. Floor does more than just butt up against the rear sill.

 

[hollowbase]

The rear floor is sandwiched between the rear sill and sill cover. Floor does more than just butt up against the rear sill.

So the sill goes under the bed and the cover goes over the sill and butts up to the bed?

 

[Living in the Past]

The pre.ambulance doors the floor went all the way back, then bent over and came half way down the sill. Not sure how far back the floor goes but probably to the end of the tub or close. It's resting on the rear sill. The cover goes over the floor. The floor is the sandwiched between the two. If it just butted up to the sill if the weld crack the floor could bend down. When removing the cover should be careful not to cut the floor if possible.
This is a picture from a thread on sill replacement here on Mud. You can see the floor is bent over and ends about half way down. I have a 10/75 and with the ambulance doors it doesn't appear to fold over. On the earlier rear sill the horizontal section is offset for the floor as seen in the picture.