Engine casing stud stuck

After the last nightmare with the castle nut (took 2.5 hours to drill out), I now have another problem on the other engine that I am doing for someone.

The longest engine casing stud (the one near to the kickstart shaft) appears to have a load of rust/corrosion around it and won’t shift.

I have tried soaking overnight in WD40 and heating the casing but it won’t shift.

Any ideas ???

turn the engine barrel facing up in a vice and fill the hollow swing arm casting wiith wd40.leave for 24hrs.use a pilot and large drill to remove the flat head off the clutch end of the stud and drive it out toward the flywheel,they shift better that way coz the threads of the stud grip the corrosion otherwise

OK, cheers for that Vespadoctor.

I’ll give it a go and let you know.

The last one that stuck on me, had to be drilled out I’m afraid!as hitting it just expanded the bolt in the hole which stuck fast,I just drilled the head down and left it,not perfect but it dosen’t leak oil.
it tends to stick through the cases,if you do get it out, cover the new one in grease for next time!