I just replaced that exact same roll pin on my 1650 last weekend. I was able to remove a small piece from the top side and a small piece from the bottom, but then there was still a big piece stuck in the middle. So I ended up removing the right side foot rest and the outer rockshaft lift cam thingy which also had a broken roll pin. Then I sprayed a lot of PB Blaster on the rock shaft arm and was able to slide the big dowel out threw the right side of the frame just enough so I could swing a hammer and remove the rest of the roll pins that were stuck in the dowel. Hope this makes sense and helps you out... Oh and I also cursed a lot of swear/cuse words
too, it didn't help much LOL
Forgot to mention I also removed the pin from the hydro cylinder and flipped that bracket up out of the way.