well, I've had some limited success. I used my vl5.9 install on my vm. I ran xconfig and ticked the 'Generic IDE' and 'Genereic PCI IDE' options (which were unticked in the supplied .config file) in the atapi configuration section. I recompiled the kernel, copied it onto my usb stick and then into my 5.8 installation and ran lilo. I botted using the newly compiled kernel and it booted fine. I'll have to experiment which is the critical option but it seems to be one of the two, assuming that the installation 5.9 kernel is based on the supplied .config.
I'd like to build a new install disk. As I said, I could copy the files onto the HD, add the new kernel. Is there software which can create an iso image? How do I ensure the image or cd is bootable?