the LD340 manifold is a square bore. That air cleaner will fit Holley or the large AFB/AVS carbs. The stealth carb, my choice, would be a OEM 750 AVS off a 68-71 HP 440. Most LD340's also had a Chrysler PN cast in. Choke is the only problem. Sorry, I just noticed the "Aftermarket". The 71 air cleaner should work with Holley and 68 and newer Carter and Edelbrock Carbs.
