Swap from LA 273 to magnum 408 water pump and cooling

I have read some heads interfer with the alt in done setups.

If it was me I would get the stock parts cleaned up and mock it all up before commiting

If all the accessory drive parts fit like stock you should be good to go.

Btw if you plan to use your OEM radiator be sure to have it disassembled and rodded out. Don't want to put old radiator crap into your new engine.

One of the nice things about using year correct parts on your car is in the future you need a 67 part you ask for a 67 (or what ever year your car is) part. Only change is internal engine and block (motor mounts, flywheel / flex plate, harmonic ballancer etc.)