More 65 Valiant 273 to 360 swap questions

Going with a mild cam, intake, 600 Edelbrock, and headers for now and probably this fall pull the engine and do some upgrades. For now I have the 8 3/4 rear bolted in and need to pull the 273/904, prep and paint the firewall and front half of the underside, get the 360, and tf ready to install, and on, and on it go's! I'd like to swap the 727 for a 904 but can't seem to locate one out here. Imagine that.