Also for
@Shel_B : water pumps jobs kinda suck balls on these solely because several bolts are likely to be rusted and break when coming out.
I only mention it because if you come across a nice rig but spot any weeping, milk it for all it's worth to get the price down.
If you're lucky the bolts snap off into the timing cover a bit, then you can slip custom bushings into the cover to guide your drill bit. I actually made custom bushings for this purpose -- I honestly don't know how guys without a lathe approach this problem.