If you set your sat nav to GU31 4AG then you may not end up at the Register Office, but you will be on the right lines.
You’re heading for “The Old College”, which you can find if you zoom in (click it 5 times). For a bit of fun, go into Street View. You’re getting close if you can still see the red marker.
Drive clockwise round the B2070 - College Street, Station Road, and Tor Way until you find the turning into Grenehurst Way. Then park in this road or find a space in the car park on the right.Google directions