Errrraaattttaaaa in my previous post. Fixed below...
3. Ok, let's assume you want to build pretty much what RedHat shipped with.
In my case that's the i686 uni-processor build. So here goes...
cd /usr/src/linux-2.4.18-14custom
# edit Makefile to set EXTRAVERSION to what you really want.
make mrproper #<--- ya really should do this!
cp configs/kernel-2.4.18-i686.config .config
make menuconfig
# in menuconfig, do nothing, just EXIT and SAVE.
# Doing this will create a "good" autoconf.h file.
make dep
make bzImage
make modules
# be root for the rest of this!
make modules_install
mkinitrd /boot/initrd-2.4.18-14custom.img 2.4.18-14custom
# copy over the kernel files to /boot, as required.
# reconfig lilo and/or grub appropriately.