One other parameter to consider: I recently purchased from Univair new engine mounts. I was offered "new old stock" or "new new stock". The price difference was negligible. The "new old stock" is rubber that has been sitting around for decades. I don't know that the "new old stock" is any harder or dried out than the "new new stock", but for a few dollars I was not going to take a chance.
Glen Glen Davis 917 297 1111 www.ishootpictures.com
