Re: 78 f150 from a 351m to a chevy 350???
Mos of the swaps I've seen, they used the chevy tranny and adapted the linkage. You've all ready mentioned the motor mounts, your next concern is the drive shaft.From there, for that vintage, it's pretty much hoses for the coolant, and maybe shifting around your wiring and exhaust match-up. I've personally haven't ever made a badge switch. What's the possibility of a swap so you can stick to the blue oval? It's not that I'm badge loyal, but staying with Ford generally means less surprises.
Chewing on asphalt and drinking dinosaur wine