We dragged my donor car out of a bramble hedge as it was the only way to get it out, once out we found that the brakes were locked, but after cutting the brake pipe (rotten) it took the pressure off enough for the offending wheels to turn.
If before you drag it out you can get to the handbrake mechanism on the back of the disc, you might be able to release, or at worse case cut the cable, there's just about enough room to get under the back end without having to jack it up
Good Luck
Brian
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