So, I take it that means I'll post up some spring data that I acquired through exhaustive research......no problem, got it!
If you want to see MVMS (Motor Vehicle Manufacturers Specifications), the list of B-body Caprice/Impala "specs" is long:
http://gmheritagecenter.com/gm-heritage-archive/vehicle-information-kits.html
Caprice:
1978 through 1996 Chevrolet Caprice (some years not listed)
Impala: (some years not listed, don't recall last year of Impala B- production before 94--seems like it may have been 1984 or 1985)
1980 Chevrolet Impala
1981 Chevrolet Impala
1983 Chevrolet Impala
1994 Chevrolet Impala
1995 Chevrolet Impala
1996 Chevrolet Impala
Regarding springs, the MVMS data provides spring & wheel rates, measuring height (called checking height), and spring coil ID, but no wire size or turn count information.