Larry - those rivets are a pain to set I agree. I ended up just mashing mine over with the smooth part of the vise after driving a punch into it to get the mushroom started. I didn't spring for the tool. Speaking of springs, what's the story on that vent spring? No way to cut the new in half and do both windows with one...lol?
I hope that you are planning on publishing this book when you are all done. You can put "How to restore your Chevy Pickup" out of business!