Collar, 8

I followed the instructions on Youtube, but I used an Impact drill and ratchet set. The hardest part is assembling the screw on the lower part of the paddle. It helps if you have your snow blower against a wall or something else so that it can not move b/c you will need some strength to push the screw threw the pre-drilled hole to the 10mm nut. I used a vise grip to hold the nut do to the lack of space and with my impact driver started to thread the screw to the nut. This part took about 1 min on one side and 10 minutes on the other side. I guess I got lucky the first time. Changing the scraper blade took about 4 minutes start to finish. It will help if you have needle nose pliers to remove and reattach the spring on each side. The instruction on you tube were very helpful. Hope you find this information helpful.