A 71 is a 3512100, the only cast-iron 340 intake in 71. They slid that intake under a TQ to make the second most powerful factory 340s ever built. It was a spreadbore, so you will need an adapter to bolt a sq-bore Holley on to it. And it is a hi-rise so you will need a proper throttle cable anchor, and possibly a new throttle cable,and if you don't already have one, the proper Mopar adapter on the throttle arm.
Don't fudge the hook-ups cuz if it fails you may get killed if the throttle sticks at WOT.