Google is your friend here. It's an M14x1.25 thread (
VERY MUCH standard) and you'll need a full helicoil kit for that size. BTW the Helicoil kit includes a special tap that references off the remainder of the existing threads and due to the length the piston in the cylinder you are working on much be at the bottom of the cylinder. It also contains 3 inserts of different lengths and the kit number is 5334-14. It's not cheap but they work better than any knockoff so I always spend the money for Helicoil and regard those who try to cheap out as FOOLS. Because if you F up on this you will find a new cylinder head is a very expensive part to replace.
Finally if you are doing this on engine use lots of grease to retain as many chips as possible, and play on filling the cylinder with acetone and vacuuming it out with and Air compressor powered vacuum. BTW, these are commonly contained in a Vacuum Colling System filler kit, another maintenance item I consider essential. NExt you will want to use air thru the spark plug hole to blow dry the cylinder and hopefully blow out any remaining chips. I will also note that once you have that cylinder totally clean a shot of motor oil into that cylinder thru the spark plug hole is needed and you will also need to change the oil immediately because it will have acetone in the oil.
Link to install video
View: https://www.youtube.com/watch?v=-qMpf9O83OQ
PS; alcohol (Vodka), Methyl Alcohol
, Rubbing Alcohol, or as a last resort Gasoline are suitable substitutes for Acetone. What you want is a fast drying solvent that will allow the cylinder to dry quickly and completely. Also take note if you are in a humid environment Air Compressors do accumulate water so make sure you run the air long enough to evacuate any water before blowing out the cylinder.
PSS; Yes, on a pushrod engine like the SBC or Ford Windsor I would pull the cylinder head to do this task. Unfortunately Ford doesn't key their Crankshafts and that makes removing the cylinder head a rather time consuming and very precise process. So doing it on car is the easiest approach and with enough effort to insure chip removal you can succeed almost every time. However it is possible to miss a chip and that could result in a scored cylinder or perhaps damage to the turbocharger. So do NOT take any shortcuts on cleaning the cylinder out.