There is one avenue that you might care to consider, sacrifice the studs; they are after all easy enough to replace and the least costly. The head gasket provides the obvious place to do the deed providing as it does a good sixteenth of an inch to put a cutter down.
I’m lucky, I have my own milling machine and that would be the best and safest way of doing it. It might be possible, with care, to do it by hand with a hacksaw or even jury rig a drilling machine. But even with the set of the hacksaw teeth ground off there is the risk of marking the machined faces. If therefore you were not totally confident I’d say entrust the job to someone who has the know-how and equipment. Sadly, until I get my new workshop up and running I can’t offer any practical help.
With the head and cylinder apart any decent press should be able to deal with the stud remains in the cylinder head. The cylinder casting is slightly more of a problem as each stud would need careful setting up so that the stud remains can be drilled out without damaging the threads in the casting.
This is not the first time that this problem has come up and I’m wondering how much extra it would cost to have sealing ferrules(?) as fitted on the head gasket to seal the bores also fitted around the water holes and stud holes. My feeling is that this would reduce water creep through the asbestos core of the gasket.
One final point, I am a great believer in anhydrous lanolin (wool fat), after all when did you last see a rusty sheep? Any good chemist will be able to get you a 500g tub that will last for ages. A thin smear over any surface will all but eliminate the risk of corrosion. I learnt its usefulness when sailing and anything that can resist seawater has got to be good! It can be diluted with white spirit and brushed on exposed parts or ones that are to be laid aside for long-term storage. It is also brilliant for protecting brake pipes and the like on the car and even helps, (for those that are compelled by ‘er indoors to do DIY), with household chores, driving woodscrews and the like.
