Anyone have permission to privately owned fields or similar that a few people could go and have some fun driving about in, vehicles with rear drive and optional 4 would be better suited to what I have in mind. Wiltshire/Dorset would be ideal but would consider further, would be happy to top up beer funds

Find a local grass track club maybe. Most of us don't generally drive about in fields unless it's for work, camping, LZ meetings or we're lost ..