hypothetical engine swap question

Inspector71

My "forced" retirement are going to slow my plans down but, I am almost done with the shell of my 68 Barracuda. It had a slant six and a built 360 will replace that. I have a 413 Wedge, once it's built, for my 66 Sport Fury and a 440 is going in to my 68 Charger. I have the cars and motors. All need rebuilt. The Charger is from Missouri so it has the most rust problems. The Barracuda had almost none. I removed the entire front and rear suspension, and all parts, until there was nothing under the Barracuda, not even the gas tank, but me and some spiders. I sanded down the entire underside, by hand or hand tools, and then primed, painted, and clear coated it, stem to stern. Never did this before.