How do I revert back to kernel-headers-2.6.40.6-0.fc15.x86_64 ?

[Dean S. Messing]

Yesterday I updated by F15 system. 
Three of the updated packages were

    kernel-headers-2.6.41.1-1.fc15.x86_64
    kernel-devel-2.6.41.1-1.fc15.x86_64
    kernel-2.6.41.1-1.fc15.x86_64

This turned out to make rebuilding the
VMware modules a MAJOR pain, and today I
noticed that VMware is loading an entire
CPU---with nothing running in
the Windows XP client!

So I intend to revert back to my "2.6.40.6-0"
system. Evidently, kernel-headers-2.6.40.6-0.fc15.x86_64
was removed in the update.

So my questions: 

1) How do I remove the 2.6.41.1 headers and
   re-install the 2.6.40.6 version?  When I
   go to erase the current headers, yum wants to
   remove a boatload of other stuff that presumably
   was built against these headers.

2) Can I have two sets of headers on the machine
   at the same time?

3) If yes, where can I get the 2.6.40.6 version.
   Yum isn't finding it in "updates"?

Thanks.

Dean