Factory XHD springs for A-bodies are 110 lb/in, not 140. SS springs start at 140 lb/in and go up to 160 lb/in.
Factory bumper height is listed here, which will give you the basic factory ride height (loaded). Full size version here
The 1970 Hamtramck Registry - Chrysler Passenger Car Bumper Heights 1965 thru 1976 Slideshow
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Instructions for getting those heights are here
The 1970 Hamtramck Registry - Chrysler Passenger Car Bumper Heights 1965 thru 1976 Slideshow
View attachment 1715962218
