67 to 74 disc brake conversion, PLEASE HELP!!!

p.s. still no pics of the brake assembly but was wondering if anyone would be able to help me with this, the guy I bought my dart from said that it was the original 273 engine in it but after talking to a cpl of guys I know everyone seems to think that the motor is bigger than the 273 here is a pic of engine (not the best pic but any ideas)

EASY to ID Mopar engines. Start by cleaning a looking at the front of the engine block immediately below the head / block parting line on the driver's side of the car. There should be a long number there, I don't recall, I believe it's something like the 2, 3, 4 digits will have the engine CID.

Your photo is not showing up, 'least fer me.

There are also casting numbers on the side of the block

http://www.yearone.com/updatedsinglepages/id_info/mopar/mopar casting numbers/castingnumbers.html

http://www.rosevillemoparts.com/reference_castingnumbers1.php