have i got some bad news about my turbo

while working to solve an exhaust leak (which my father and i hoped to be just some bad gaskets which we think it was they were burnt and broken) we removed the exhaust manifold and turbo unit from the rest of the engine but not without a struggle then we put on the new gaskets put the manifold back on started tightening the nuts back up

got them all on and my dad goes to check them and the last one "eeerrrr pop!!" the stud broke in half almost, leaving part of the stud still in the engine

so of course it had to be the last one to break or otherwise i would be driving my good old turbo brick

but how hard is it to fix? i know you have to drill it out but is there anything i should know before hand?
plus it is the one closest to the firewall on the top and there seems to be enough space to get a drill in without taking too much apart

what do you guys think?

thanks for any info and help it is much appreciated

matt
2-240 turbo and dl
3-850 turbo and 2 n/a
1-164E project car