There is no drain plug on the rack and pinion assembly. What are you so worried about? You never started the engine so all the coolant was in the reservior. You drained that, plus whatever came out of the disconnected hoses. So there’s no coolant left in the power steering system. If you had started the engine, then you would have pumped the coolant throughout the power steering system and then it would need to be flushed. But since that didn’t happen, you’re good to go.
Tester