Book says 120mm (5") from top of axle case to the chassis rail with load on the front so you're probably not too far off. Could be wind up in the bushes - slacken off all the spring and shackle bolts making sure the pins rotate freely, hopefully the front will sit up giving you more than the 5" of clearance. You should have to get a couple of mates to sit on the front to get the clearance down to 5", then tighten up all the bolts. If you can't get enough clearance then the springs are probably shot - either gone soft or rusted up.