Phil, In trying to find the spring in GM Partswiki, it seems the correct spring is GM# 3766370 - 6-1/4" free length, 30 coils. Searchs on the web don't show any NOS or reproduction springs that I could find. Further generic searches in various FLAPS keep returning a reference to a Dorman 59207 Spring Assortment (4 different springs) that may contain one that will work. Best of luck to your friend!
