Hey Thanks Crummy! The measurements and pictures really helped out. I was going to locate my shock mounts further up the curve but saw where the bed cross sill is located in your 3rd picture so that put an end to that idea. I do find it interesting how that bed cross-sill right adjacent to the mount is only seated on one side. You would think it would have a wedge underneath it but I can see the 70 plus year wear marks in my frame where the one side wore into it. I guess it worked for 70 years so no need to create a wedge shaped shim for it now. Is there now bolt going through the cross sill into the fame? I assume not because I don't see a hole in my frame that location.
Based on your rear mounts I think the aftermarket rear mounts are wider so I need to factor that in as well, or reshape it slightly. I think they only sell the one mount style for both front and back because I have never seen a narrower aftermarket one like on yours.
BTW- love the stance on your truck and the flat finish. I also have a 3" sids dropped axle and posies all around. I do have 2" blocks on the rear as well but no sure I will need them.
Once again, thanks for the help. This group never fails to impress me with the knowledge and friendliness it provides.