Q: How do I install self-signed SSL certificates on two IIS 6 websites on the same server where both sites use port 443 and are configured with host headers?
A: Multiple SSL sites on a single IIS server using host headers.  <- the answer. 
Basically, use SelfSSL or SSLDiag to create a cert with CN=*.example.com, then [...]

Q: How do I install a self-signed SSL certificate on an IIS 6 website?
A: Use the SelfSSL utility that comes with the IIS Resource kit!
http://codeforeternity.com/blogs/technology/archive/2008/02/15/creating-self-signed-ssl-certificates-on-iis-6-0-and-windows-server-2003.aspx
 
Q: How do I install self-signed SSL certificates on two IIS 6 websites on the same server?
A: SelfSSL.exe is bugged.  Install SSLDiag and use its embedded SelfSSL tool.
The problem with two [...]