Technical 48 oldsmobile rear springs

Where do I start looking to find shorter coil springs to lower rear down. Called couple of big name companies and no help . 1948 oldsmobile series 76

 

Torch the very bottom turn evenly. That'll drop it 2-3 inches. Do it very non-aggressively so it doesn't warp ...

 

https://www.jalopyjournal.com/forum/threads/1948-oldsmobile-lowering.1095619/
Short thread a while back, might help if you hadn't read it.

 

I'd have thought that they could have wound a shorter spring using OEM as a template or use substitute coils

 

Stupid question, what is intermediate coils

 

That will kill the Temper in the spring.
Some people might get away with it, still not correct.
(I used to make prototypes at a spring company.)

 

Did you try Eaton Detroit Spring ?
https://www.eatondetroitspring.com/