FTF!!! @ 8:15am
Saw this pop up just before we went to bed last night and was up early this morning (could not sleep) so thought we'd pop out and find it as it's not far from home.
The stated co-ords put the cache at the side of the road - we used our cachers eye and the "now, where would I hide it" train of thought to locate the cache after a short search. Nice hide!
Spotted the stone with 1797 on it although it's a bit overgrown.
I took the following reading at the cache: N52 42.254 W002 41.659. GPS was indicating it was accurate to within 20 feet and plotting it on Streetmap it looks about right.
I found a picture of the tunnel entrance from 1880 at http://www.btinternet.com/~canals/area/severn/severn/shrew08.jpg if anyone is interested.
There is also parking at N52 42.281 W002 41.57 if the suggested parking is being used.