My son's CRF 100 needed linkage and swing arm rebuild. I bought the Pivot Works kits that replaces the OEM plastic bushings with steel needle bearings, seals, and roller pins. The needle bearings are super tricky to install. The needles are in open races with no retainers, and want to just fall out. For the linkage I used the dust caps as guides and just pressed them in. I Still had a few needles fall out but wasn't a huge problem. The swing arm is really hard. The kit comes with 2 bearings to replace each plastic bushing. I've heated the swing arm and froze the bearing but still having a hell of a time getting them pressed in. Question 1. What are the tricks to getting these bearings pressed into the swingarm? Question 2. Why are there 4 bearing seals instead of just 2? Question 3. I think it might have been better to just buy new plastic bushings?