Yes this has been asked before, and it takes technique. So don't feel bad on your first attempt. Spend some time with the search feature on this board for older posts. Hopefully somebody can give better "instructions". This is what I can add.
1) Stretch it out so when you let go, it is about 1/2" wide (sprung).
2) Push one end into the groove, and don't let the other end get in the hole until the very end. About 1/2 to 3/4 of a turn can be in the hole at one time.
3) Work around and push it in the groove a little bit around at a time in the circular direction.
It will go in the groove without excessive pressure if you are doing it correctly. So don't force it.
From the Ross Piston Instructions (web):
Quote:
Spiro Lox installation may be facilitated by grasping each end of the lox and pulling the ends apart a MODERATE (approximately ˝”) amount. This will cause the lox to resemble a small coil spring. The lox can then be “spiraled” into place almost as if you were screwing them into the groove. Be sure that all lox are properly seated and that they exert radial pressure against the lox groove. You should not be able to spin the lox by hand after they are installed. Most Ross Racing Pistons come with double lox (four lox total per piston – two at each end of the pin). Be sure that the correct number of lox
are installed in each piston.
