It may be worth a mention if any LS430 owners are considering a conversion to springs. Rockauto now have front and rear complete struts ready for a straight swap at less than £500 including taxes and shipping for the set.
I would nip into a place that sells batteries and tyres etc and ask them to do a quick battery test. Sometimes disconnecting the battery earth for 10 mins can reset everything but if it's duff you'll need a new one asap.