Knit & Stitch Harrogate - where to Park?

[chocolateteabag]

Got my tickets for Saturday and Sunday but then remembered that it's in the centre of Harrogate and not at the Show ground (lots of free parking)
So where can I park all day in Harrogate that isn't miles from the centre or going to cost the earth? DP has suggested Asda but pretty sure it will have a maximum stay?
Need to make full use of both days as DP needs to feel the joy of a long weekend with DS

Ooh, I'm going on the Friday! No idea about parking though, I've always been on the train as mum lives in Leeds. I know there's a big NCP-type place nearby, don't know what that'll cost though.