We had some Calvert split mono springs that had a 22" front segment and we needed 20". Called Calvert to see if it was okay to re-drill. They said no problem!

We re-drilled them and installed and they work fine with zero issues.

I know they offer new rear spring segments to change ride height as well.

'63 Dodge 330
11.19 @ 121 mph
Pump gas, n/a, through the mufflers on street tires with 3.54's. 3,600 lbs.
10.01 @ 133mph with a 250 shot of nitrous an a splash of race gas. 1.36 60 ft. 3,700 lbs.