Just finding a workspace large enough for this size print would be a challenge. Why would you use acrylic for a backing? Wouldn't fibreboard be better? Can you even find a large enough acrylic sheet? How about glass? Then there's framing. I've been experimenting with frameless supports that clip on to the corners of photos, including the backing, mat and glass/acrylic. There are heavy duty ones for pieces over 20 inches on one side, but ten feet is ridiculous. I would be interested to hear how you resolve this.
And welcome back to the forum. Your Flickr stream is full of interesting photos.