yeah it will be a pain, luckily changing the HG on starlets though isn't a difficult job and you could do it your self on a weekend if you haven't done it before. If it has failed though, always remember to get your head skimmed to ensure its totally flat, its about £30 in a machine shop, worth doing for peace of mind and while the head is off its probably worth getting your valve stem seals changed too as the parts are only cheap and will prevent any future problems while its apart