Sweet, here is a close-up showing some yellow underneath the Chevy orange.

http://s844.photobucket.com/user/matthewronaldsaunders/media/261/IMG_1318_zpsiifxozvj.jpg.html

Mike, I couldn't find the serial number on the machined surface next to the distributor when I looked earlier today but will check again when I have a wire wheel and a flashlight to help.

Deve, that is a great article and one of the reasons I began a hunt for a 261.

Sorry, I should have included in my initial post that this one has half inch fittings, but the dowel is flush with the block. It had a bypass oil filter on it. The top half inch fitting is a galvanized plug that was drilled and tapped to fit a smaller size to the bypass. Pix below--

http://s844.photobucket.com/user/matthewronaldsaunders/media/261/IMG_1316_zps15yuhzif.jpg.html

http://s844.photobucket.com/user/matthewronaldsaunders/media/261/IMG_1317_zpsgfshczrw.jpg.html

Thanks,

Matt