Making install CD's with custom kernel

[Bill Geddes <wgeddes@wgeddes.com>]

I'm having install problems on a server I am building.  Has an Adaptec
scsi - onboard a TYAN Thunder i7500 motherboard that wants to use the
AIC7xxx driver.  Both the Woody and the SID install CD's that I built
with jigdo hang when this module is being loaded.

Is it possible to take the Debian SID install CD that I created with
jigdo, mount it, copy its contents to a filesystem on my hard drive,
then copy a custom kernel into place, and recreate the CD ISO image so
that I can boot some hardware that the SID install CD does not
recognize? 
(sorry about the mouthful)

Basically, is there a trick to using mkisofs for this purpose other than
what is listed in the eltorito README file?

Thanks for any help.