Ok so the iguana i'm probably rescueing is 5 years old and only 27 inches. I have a spare tank that im not sure will work. It is 6 feet tall, 3 ft wide, and 3 feet deep. Some guy gave it to me. Heres the link incase i read the length of him or something wrong.http://www.corhs.org/diesel.html Thanks!

if that is how big that he is right now then that cage should be good for now but you should possibly look into getting a slightly larger tank at least that is what is recammended

So it will work for a few months untill i can build a larger one? Also, he looks a bit big for 27", could it be nose to vent? Thanks!

If he's 5 years old and only 27" that's actually abnormally small. Mine's 2 1/2 years old and 3 1/2 feet long and still growing. There has to be some health issues there, I would definitely get him checked out by a vet.