So, I have just finished 2 years of repairs on my 914 1.8, and was getting ready to start running by installing new plugs, cables etc. - a full tune up kit. As I pulled my last plug out, I noticed the threads are shot on the bore hole. Why I hadn't noticed this before is beyond me... but... Is there any way to repair this without dropping my engine AGAIN??

Your best chance is to pull the head and have it repaired. Trying to do this in the car is tough and risky.

It can be done, you need to find someone with a deep reach timesert kit. Grease the tool, clean often and pray you don't get any chips in the chamber.

Would I do it? No.
I'd remove it and do the timesert repair.

Don't use helicoils, they totally suck.

I pulled a timesert once, got it fixed no problem.

Thanks for input guys.
I guess I have put all this effort into it.. Plug is passenger rear / so space is limited.
I'm going ahead with another engine drop and do it right.
Been watching youtube projects of people doing the timesert.. and - in spite of all the positive vibes they put out about blowing out the shavings, I didn't come this far to risk it.
Trouble is, with my current time constraints... I bet I'm not driving it now for another three months or so. Dammit...

Ok... UPDATE. (and why are stupid things happening to me lately! - I don't even want to metion what happened to the diswasher recently, thanks to me...).
Been retracing steps from Saturday morning, and reinspected all pulled plugs, and guess what! - one plug has a timesert screwed on to it! It appears I pulled out a previous repair. Hopefully, all I need to do is match it and re-insert!

Big whoop for a big blushing idiot...
(why am I rushing everything thewse days!!)

It not worth buying your own tool for one plug hole, if you use a machine shop ask for the timesert only, many still use helicoils. Don't fall for BS that they are just as good.

They are equally as good, but used for different instances. They are often used in place of each other but shouldn't be.

The threads for the inserts are not normally the same, so if it's been timeserted, then you'll have to use the same thing. Also, you can't just get an insert from someone. You need the tool to thread them in as well. Some also have a "stake" function at the end.

For spark plug holes that have not been messed with before. their are inserts that use the original threads (whatever is left) to start the die in and then cut their own new threads in their place. You then use a different tool to cut a small top relief, then the third tool to screw the insert in and set it. Very trick setup but about $250 for the tools.