Dongas---Yes, you only use the normal body to frame mounts. I do not recommend that you secure the "wells" to the frame--there is no need to do that, and it will cause other issues. Whenever I have channeled a car, I don't even use the normal body to frame mounts. On one car I drilled and tapped the top of the frame every 8", and drilled directly thru the floor pan to bolt the floor to the frame. I used the 2" x 1/8" thick fabric webbing that has an adhesive backing you peel off one side and stick to the top of the framerail for an anti-squeak insulator. On another car,which had a glass body and laminated plywood floor, I was afraid od "tweaking" the floor by pulling it down to the floor with bolts---this would have caused issues with body flex, and consequently affected the fit of the doors, as it was an open top roadster. ---In that case, I set the body on top of the frame, and bolted a series of short angle iron peices to the floor (they lay tight against the inside of the frame but were not bolted to it).---Then I bolted thru the floor and the angles and drew the bolts up tight, then welded the angles to the inside of the frame rails.---That essentially gave me a good solid connection between the body and the frame, didn't "tweak" the floor in any way, and still allowed me to unbolt the body from the frame if I needed to. ---and yes, as far as the solid models go, I really am a "pro"---thats what I do for a living.
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