I would agree with Geezer here (I usually do). That's the correct part number for the kit, so the problem is either in whether or not that's actually what you got, or the shop messed up the install. There's a break-in period where the springs will settle a little bit, but that shouldn't make the whole thing softer.
"My yellow, in this case, is not so mellow" -Jimi Hendrix
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