Not sure on value, but we need pics man!
Quick ebay search does not show any sold recently, but non 429 cars sold for low 20's restored. 1970 thru 72.
On all fords with the 429, the Torino was closest and other than a few "King Cobra" cars, looks like they bring in the 30's to low 50's fully restored and type of car (ie Mustang brings more than the others)
So, not sure on value, but if they are like the Elky's, they don't seem to be in super high demand.
Searching ebay on El Camino's 70's with the LS5, shows 20's to 40's, with 40's being no sale at dealers. Project Elky's in that same category struggled to get into the 10's.
Exception would be the few LS6 El Camino's of course.
Hope that helps.
Rich