Sharps40

Just looked at my 37 dodge 4 door hump back.  D5.  5 passenger.  All original mounts.   Same location on mine as yours. 
 
1.  Simple bolt.   Head inside frame.  Nut inside trunk.
 
2.  Bolt goes thru the left and right lower legs of the x brace between trunk and rear seat back. 
 
3.  Stacking is in this order from head in frame to nut in trunk.
 
A.  Bolt up thru top of frame rail
 
B.  A rubber doughnut over bolt shank and resting on top of frame
 
C. Body sitting on top of doughnut 
 
D. Rubber doughnut over bolt shank inside trunk and resting on the floor/foot of the rear seat x member
 
E. Big steel washer,  1/8 or more thick over bolt and on top of the trunk doughnut 
 
F. Nut pulling the washer down to secure the assembly.  
 
Simple set up.  Basic hardware.  
 
Luck

Well, word I'm getting from several other forums is the suspension parts will not likely be worth the hassle to move 500 miles from the shop to here and then advertise and over the road ship such large/heavy items.  We'll have to make a call later but 9c/lb for scrap iron is the final option if we decide to pull and replace with more modern components.  Thanks all.