On the Biceps, I glued (e6000) on one side, and used industrial Strength velcro on the back side. They are very tight so I had to remove almost all the lip. They Stay in place but it is a little dificult to flex. They have a strip of double sided velcro that attached to the underside of the bells. I can move freely but it is dificult for me to bend more than 90 degrees my arms. I am thinking on probably cut them a little shorter by about 1/2 inch.
The straps are black but look rubbery, so I used the same paint I used on the armor.
The back plate needs modification, you will need to add the sideflaps so that they properly attach to the front plate.