Any way , Excuse the bad photies , the drillin went off center ,
tried to counter screw , which ,,,, Yes .... It broke in the Now off center
hole ........
Nut and mig welder......Hold a washer round the broken nipple and weld it to the nipple, Then give it a decent knock with a hammer. Now weld thro' a 10mm nut onto the washer,let it cool and hammer again, then fingers crossed it should screw out with a spanner.