This is the new wheel installed now, it is very easy to do, but here are some steps:
mfrench has found a really simple, highly effective method for popping off the wheels:
Hold the arm so that the rubber bushing end is up. Place the axle tip end on a hard surface, I used my kitchen counter top.
With the tip of the axle down, put your thumbs on either side of the inner wheel, near the pressed in bronze bushing, and just press downward with your thumbs as close to the center axis point as possible. This takes the load off the idler arm, and off the outer edges of the wheel too, so you don’t “taco” your wheel. The thing pops right off.
And a similarly simple way to put it back:
Secure the opposite end of the axle onto a hard surface, the press-fitted end, and let the arm dangle below – again, I used the kitchen countertop, over the edge this time.
Use a pair of wire strippers at 10ga setting, held closed. Place the 10ga hole over the circlip (that is pre-positioned on the axle), and press down. The clip will slip right on because there is an even force from 360º around it.
If you seat it on to far, you go back to the removal phase, and barely push, which will loosen the fit.
Neither of the removal and replacement techniques will stress the wheel or the arm.”