I want to install Yosemite on a MacbookPro4,1 that has a broken firewire system I have been able to run snow leopard by executing

rm -rf /System/Library/Extensions/*Firewire*


I think need to sneak this somewhere into the yosemite installer..

Or perhaps install yosemite with a different laptop and then swap the drive into my old firewirebroken laptop after running my above command.

The yosemite upgrade hangs around the halfway point.. 

I can't justify buying a new logic board for this machine since I don't have a need for firewire.  Just want to hack the OS into functionality.
I don't really see a question here.  What is it you need help with?  You should be able to get 10.10.1 either by (a) installing it on a working system and swapping the hard disk or (b) installing it on a working system, take a Time Machine backup, then restore said backup on to the broken system.