I have just finished providing the original Douay-Rheims side-by-side with the Challoner revision of the book of Revelation. The original Douay-Rheims I have put in modern spelling, but I kept it as close as possible to the original. sites.google.com/site/aquinasstudybible/home/revelation/douay-rheims-bible
I am also working on providing all the wonderful footnotes and commentary in the original Douay-Rheims Study Bible! It has already been transcribed and on the market by someone else, but what I am doing will be freely online for everyone to use!