What is the diferance between the 2.8chevy 173 fwd engine and the 2.8 rwd engine?

I was wondering exactly what the diferance was between the engines? I need a 2.8 chevy motor for a 4 wheel drive izuzu., My friend has a 2.8 chevy motor but he said it wont work because it is for a front wheel drive car. Can I just switch the oil pans or is there a big diferance between the engines?