I've used 'splash pans'  to describe those flat things on the inside corners
of your back bumper.   Well, were there at one time.   The  pan under the
drivers feet I heard called belly pan,  the Parts List calls it 'Cover plate
under pedal linkage'  :

211 703 611  -   to chassis #  20 - 117 902 (March 1955)  LHD
211 703 609 B    from 20-117 902  LHD

for all post barndoor splitties it's the same thang.   

 Time to put the pan back on the 61,  taken off to replace something. (?)
  It hasn't been driven since I hauled wood 2 weeks ago,  as it's so drafty
from the rust holes brrrrr  .    Sorry, no extra pan.
 

                                                      
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