A ride from Mossley would be OK. 25 miles each way isn't much. However, I favour the parking up in Wilmslow option - I've done that before with Mrs North in an attempt to get her out on her bike. If you go down the A34 to the end and turn right towards Wilsmlow you'll come to a roundabout. Turn left (Royles is on your left if you want to look at some bike p*rn). Drive along that road and you'll see residential roads on your right and left. I've parked up in one of those before.
If you rthen jump on the bike and head down the road you have just come from (i.e. the one from Royles), you'll come to a mini roundabout. Turn right. This is the Knutsford road. You can either follow this all the way to Knutsford (it's not too bad, but can be a little busy), or head along for a short time and take a right to Mobberley (it's signposted). The lanes can be a bit confusing round there, so you'll need a map to make sure you can find your way to Ashley and then to the Park. I sort of ride round until I find where i intend to go, and then carry on!
Hope you have a good day!