Having collected the numbers from the Mural Trail you will find the cache at;
N50 30.F B D W004 18.C E A
You can walk to it from the car park, about a 25 minute round trip (doesn't include search time) but you can park closer should you wish to but don't park in the lane accessing the bridleway.. The bridleway does have areas of loose stones but it is generally good underfoot and fairly flat.