tap larger threads in block for oil pan

[BlueDog]

I'm working on installing a replacement engine in my '89 Jetta. I found that two of the threaded holes on the bottom of the block have stripped out threads. The two holes are the hard to reach ones near the flywheel. Apparently the PO had some trouble installing these and wrecked them. I'd like to correct this by somehow not removing the flywheel. Anyone of any ideas?

[BlueDog]

To be a bit clearer, the threads that are stripped are in the aluminum part nearest the transmission.

[BlueDog]

There is not enough vertical clearance to drill holes and tap threads to the next size larger. Same with heli-coils. The sheetmetal is in the way. Maybe I could install self-threading bolts into these two stripped out holes.

[82vdub]

Use helicoils. You may be able to keep the threads as they are, screw in a helicoil and use a slightly smaller bolt size.

[Fatmobile]

Yeah I try to helicoil those before a rebuild so they don't strip out later.
You can probably put the tap in a 1/4" drive socket to get it up there far enough to tap it.
While helicoils are kind of spendy the first time, when you have to buy the tap and tool,..
it is a common thread and might come in handy later since those small ones are easy to strip out.