Hopefully this will work here
Full album here > https://1drv.ms/u/s!AigNPuwBlwA-i881RoEkgl8tY4b3Jw?e=g42Vfy Includes measurements.
The pulley is threaded with 2 m8 threads, so you can bolt the tool to it.
Welding is a bit rough on this as it was done with a welder that wasn't working as well as it should have been, but you should get the general idea of what you need. The larger hole needs to be big enough to clear the washer on the pulley, the smaller one you need to make to suit your socket for the pulley. 47 and 34mm respectively should be fine from the measurements taken today. Overall diameter of the bit to fit inside pulley can be 94mm, the distance between the inside edges of the 2 bolt holes comes in a 67.77 mm (you have a bit of play here as it only had to allow you to get a bolt into the holes in the pulley)
As said, he made this with access to a pulley as access on the car was just too difficult to do much else (brought another pulley off eBay).