Sorry, maybe I wasn't clear. I meant that since you're dropping the squats what you might be able to do is run a routine similar to the 5x5 but using the rack-pulls instead of squats. Also, since you're not doing deads, either, you'll need a suitable alternative for them to drop into the Wednesday slot.
I guess, without a squat rack, GM aren't an option. Maybe pullthroughs would be ok but you'd need a meaty stack to make them your only sub. Basically, you're either going to have to put a lot of thought into designing a sufficiently challenging routine to emulate the madcow 5x5 or come up with a simpler approach to work your body piecemeal.