Magnum engines in A-bdy ???
I just did this swap. I got a dual plan air gap intake off ebay $150.00 on a tight budget you can't beat them. There's going to be some modifications needed to run the cheaper headers! You must! I repeat, must grind off the ram truck engine mounting points that are on the upper middle of the engine block. The headers will hit and not fit if you don't causing lots of head aches!!! Ask me how I know! So please do yourself a favor and grind them off before you install the engine! It's much,much easier!!! And get the motor mounts from mancini part # SCHA67LA
http://www.manciniracing.com/19abv8to34re.html
Will save you time and head ache because they are NOT the same as 273-318 they are 340-360 only and will not interchange!!! Again ask how I know. LOL I learned the hard way! I hope you kept the flex plate from the magnum your going to need it they don't interchange between the magnum and LA's it'll hook up to the neutral balanced 273-318 torque converters but you will need to enlarge one of the torque converter bolt holes to accommodate one being a little off center that is normal for this conversion! But in the end you'll love the change it'll make in your car.