1972 Canadian H-Code 340 Dart Swinger Special Resto - Finally started!

This is a great thread with a lot of useful information. very helpful for a rookie like me. After reading through the whole thing twice, I started tackling my quarter replacement on my 1973 Dart. I have all the old quarter removed, but I have a question on test fitting the new AMD quarter. What is the trick to getting the quarter installed under the roof skin? with the tab on the front part, and trying to get it up over the window channel, while getting the ends in the correct place, it's becoming quite frustrating.

Any pointers to make this less stressful?
Thanks.

quarter3.jpg