Ok hello to all that read this, I'm here just like most for not only information on how to repair my truck , but also to be part of something that has been & will be. With that said here is my problem in short I have a 97 f350 crew cab xl stock everything. 351 windsor in it I do believe. as of right now He is broken down pulled apart in my garage. Due to a much requested headgasket replacement. In any event long story short I got him all apart to discover that there was someone in it before me & had broken the infamous exhaust manifold bolts (5) and two of the lower intake bolts, (of course one had to be a real pita, but in any even of course I've tried the correct route in removing these broken bolts/studs but again the year of the truck (1997) & its bone stock no way their moving...So of course I tried the next best thing (on a budget) which is to drill them out, but I went to far into the exhaust manifold bolt holes, And now I believe that I've ruined the heads is this so? If so who knows where i can get a decent set of bolt on heads ready to go. yes this is my daily driver & since He's been down I've been going deeper in dept. So if anyone has any type of information on how to handle this short of very expensive I'm open to all things... thank you in advance to all, & please forgive me for any typo's or forum rule violations that i may have done. Again I am new....thank again

 

You 351 should still be plentiful in the yards.
Get one or both heads and have them offer ones that have the bolts removed.
Use new replacement bolts for the assembly.
Clean out all holes with a Tap so they torque up properly.
This is the shortest way out of your issues and the most reliable so you don't have to go back in and do something over again wasting time and gaskets and more money.
Good luck.