1967 C10 bbc engine swap

[1967C10]

I'm getting ready to replace a 350 with a 454 in my 1967 C10. Anyone have any experience with this engine swap? My 1st concern is the motor mounts: Can I use the 350 motor mounts on the big block? If not, where can I buy big block mounts? Most of the parts stores around here don't have a clue. BTW, the '77 Suburban motor mounts are still bolted on the big block.

Also, will there be any clearance problems with the HEI, short valve covers or headers?

Any info would be appreciated as this is my first try at an engine swap.