Engine lifts

Do the engine lifts that are on both sides of my 351 remain in place full time or should the be removed if not being used?

Those are the factory install brackets they stay on. You probably cannot use them because the lift chains hit the valve covers. Ford had a special lift that could tilt the engine and transmission as it went in. There were workers under the car and one man on the lift. You would want to keep them to keep original.

@ 1:40 you can see the installation of the engine.

They should remain for factory appearance if that's what you are aiming for.  Whatever you do, don't try to use them to lift the engine.  After the engine has been in operation for awhile (and by now that's many years), the cast iron exhaust manifolds become brittle.

If you try to use the brackets as lift points, you are more likely to end up with cracked exhaust manifolds.  Usually due to combination of brittle cast iron and studs flexing more than they did when fresh.

One of those lessons learned from experience.

so they are not to be used and I am not concerned about a concours perfect engine so maybe I will remove them.  Pretty busy there already so maybe a little more room to get the hands down there when needed.