Yup.  Was very nervous taking apart my 350MHz Pentium II as well.  The push-clips really did not want to come loose.  But once I got them separated, 20-year-old thermal dust (you couldn't call that dry crap paste anymore) was replaced with Arctic Silver 5 and reassembled.  CPU still works perfectly.  Unfortunately, I upgraded the system to a 600MHz Pentium 3 (Katmai) which I also cleaned the same way before applying a removable CPU cooler.  So now the P2 sits in a box.  I don't know if I'll ever use it again.  I doubt I can even sell it on E-bay.  It would cost more to ship than I could get for it.