[Janusz]

The 427 would come into play if you were measuring from the pan to the floor, but the 2" frame to floor measurement is dependant on the suspension geometry . The older SV’s used different length shocks in the front versus the back, whereas the new chassis uses the same shock and a different spring rate. Is there a chance the shocks were switched, which would place the lower spring rate in the front?

Can you estimate the front shock length, mount-to-mount, as the vehicle is sitting with the weight on it? Also how much is the spring compressed with the spring nut (how many inches of thread are showing below the nut)?