I have two honda rear mounts. They are not the same size. Same general orientation, one is just larger in every dimension.

I pulled one off of a D16Y8 trans/motor I just bought. Tossed it into a parts box that the kid gave me, I was unaware there was another mount in there. He had a shop do a B-series swap into his civic, they threw all the misc parts in a box that he gave me. I am assuming that the larger mount is a B-series trans mount.

Here are the pics together.

 

99-00 SI rear mount.

 

the integra rear mounts are a lil longer than the 99-00 si mounts. but im pretty sure that thats a 99-00 si.