Assuming that the 2.4 kernel from that release has the usb-storage module, you can do something like this (forgive me if I'm a little rusty, but it has been a while since Redhat 8):
mount /dev/sda1 /mnt/usbdrive
If the usb-storage kernel wasn't in that release, you may want to update your kernel (or your entire distro, for that matter). Also, if that procedure works, make sure to umount before taking the drive out!!!