69 COPO Camaro Coil Spring.......code #'s ????????

[CamarosRus]

I see where RICKS Camaro parts has a long list of 69 Camaro coil springs with misc codes (i.e. YA).
There is another chart adjustment weights for misc options (???)

After having my 69 X-11 COPO clone sit too low and now a tad high, I'm still searching for "correct" spring.

My car has T-400 trans, power steering, power brakes, repop curved neck radiator, headers, no smog, iron heads, 163 intake, etc etc

Can anybody with knowledge of this subject,please help or direct me to someone who does. I would like to make the third set of coils the last set

FYI, the rear has HeartBeat City repop leafs which appear good.

The car has been driven a good 1000 miles so there was NO significant settling..........