Well, I think we are splitting hairs here. The Ford tripower has completely different air horn than the Chevy. It is pointed on the ends. Both Ford and Chevy both have the tall air horns on the outboards. The parts to build these 4782/4783 combo did not even exist until early in 1969 and these outboard main bodies were only used on the outboards on Mopars. They modified the machining process to make them mechanical secondaries. The outboard throttle shafts were made strictly for these 4783 Those other parts are just std Holley parts that they were already making. They wanted metering blocks on the end carbs that were easy to change jets. The short bowls had to be used because the rear carb would not fit with the regular center pivot bowl. The part numbers tell me Holley came up with this idea in the early 70 year. The dates on the carbs verify that. I believe Rhino on the Mr. Norm deal about him using the Chevy carbs. They did not have the idle circuit in the base of the outboards or the hole drilled in the outboard throttle blade. I could see that saving $10 in machine work in the 70’s. Mopar wanted the outboards to meter a little gas in order for fuel to stay fresh and the needle and seat to not stick.

On a side note to the OP. If you are happy with the performance of the carbs, keep them. If you want a nicely restored set of date coded 70 440 4 speed carbs, i just finished at set. A shaker air cleaner is so big, no one can even see the carbs. Even a regular six pack air cleaner is so big, very little of the carbs can be seen. I’ve got nice carbs on my AAR so I take the air cleaner off at shows. People like to see those nice Holleys all lined up.