<VV> front goil springs

[ericmpholz at netzero.com]

My '63 vert has a front k-member from a 61 sedan in it, and I want to replace the front coils.  If I place my weight on the front corners I can push it down three inched and bottom it out.  If I do the same to the rear it moves only an inch...maybe.  My question: 
Are the k-members all the same save the coils?  
I believe I should install the convertible rates coils in it.  This also begs another question:
What is the difference in the rating of each coil.  What ones are rated least lbs? What ones are rates most lbs.
On the subject of ride height:  the distance from the horizontal on the bottom of the rocker (not including the lip) to the ground in front of the rear wheel and behind the front wheel is about eight inches.  According to the General in his '61 repair book, it should bee 9 3/8 +or-1/2"  Is this correct?  I could not find anything for the '63 in the supplement.  I believe that my tire size is close to OE as I am running 185/80 R13 Firestone 410.
Any help appreciated either proved or anecdotal
 
Thanks,
Eric Holz
'63 vert (mostly)