Fwiw I was in manc yesterday at Piccadilly gardens. It was a **** nightmare. Ended up dumping the car and getting the train in. Even that was delayed. Then unwound the trip leaving at 4.15, took over an hour and a half and two trains to get back to birchwood. Then drove to woking, getting here at 10.
Manchester is shit for traffic. And trains. So either go early and park in somewhere like NCP the Grand (5 quid all day in before 9) or do the tram thing. Or the train from Huddersfield (hope you like standing).
Just make sure you have very low expectations and you’ll be fine.