Red spring- blue spring...
Old spring- new spring.
Dr Seuss... or setting a 700R4 governor? :chuckle
With the 2.87, I had the GM purple and a B&M orange spring and that gave me a 1-2 shift at 5,450rpm. When I upgraded to the 3.73, the 1-2 shift was probably over 5,800rpm - way too high...