My stealhy wieght replaces the normal flywheel nut. There are four set screws on the outside edge that bite into the flywheel, loosen them up but do not take them out since the threaded holes are staked. On the face of the wieght there should be two threaded holes, you can make a plate that will bolt to these holes with a cheap socket welded on the middle, or you can call stealhy and get their tool.
I really didnt care for the stealhy tool as it is, the flat plate if bolted tight to the flywheel does not really give your 1/2 drive tool a good bite so I took a short cheap extension welded it to the plate and ground off the excess sticking through. The stock tool is adequate for limited use but since I am constantly zipping mine off and on with an impact gun the square hole was starting to round out.