Install F8 from a mounted pen drive

[Clodoaldo]

I want to install F8. I can't burn a CD.

I have a FC6 rescue CD from which I can boot. I tried to install
booting from the FC6 rescue CD and then from a HTTP mirror but the
installation stops with a message that says something like "the
install media version is different from the version you want to
install".

I have already installed from a pen drive a number of times but this
machine can't boot from the pen drive.

Booting from the FC6 rescue CD I can mount the pen drive which has the
diskboot.img file wrote with dd as I already did sometimes. Is it
possible to continue from here, with the mounted pen drive?

Regards, Clodoaldo Pinto Neto