hello im looking to lower my hhr and came acroos eibachs site. Now they list a pro kit which lowers 1.0/1.6 rear part number is 3899.140. Now a chevy cobalt uses the same spring for a 1.6/1.8 drop which is the same part number. now the cobalt has a sportline kit which lowers 2.0/2.5. So the eibach cobalt sportline should also work in our hhr right? which would lower about 1.4/2.1. Has anyone tried this out?