There's a huge car park on Pall Mall just off Leeds Street called Microsafe Security Car Park which has been used by office workers for years, I would be amazed if they weren't planning to open as they will make a fortune being one of the biggest car parks to the new stadium, I haven't parked there for a while but there's a review on the internet saying it was £3.50 a day a few months ago, far cheaper and closer than anything in town.....

https://www.google.co.uk/maps/place/Microsafe+Security+Car+Park/@53.4141266,-2.9947202,195m/data=!3m1!1e3!4m6!3m5!1s0x487b217a3498fdbd:0x25a92577313204af!8m2!3d53.4135963!4d-2.9943329!16s%2Fg%2F11m84v81h8?entry=ttu&g_ep=EgoyMDI1MDgwNS4wIKXMDSoASAFQAw%3D%3D