Thomann Springs Tenor Sax

I bought this pack to repair my palm D# key on my Selmer Mk6 tenor. Unfortunately the hole is smaller than the screw that holds it to the key. I could force the hole bigger with a screwdriver (!) but I now worry the spring is weak at that point and I think I'll ask my technician to look at it next time I see him.
The spring also seems weaker than the one it replaced, but I'm not an expert so am not sure of my judgement.