Engine color Red or blue????

I am replacing my 273 from my 1967 Plymouth barracuda fastback with a block date code 1972 340. The top is all going to be eledbtick aluminum components from the intake, valve covers to the air cleaner the cylinder heads.

I need to decide on the color of the bottom half of the engine. I know no one's going to hardly see any color once installed it but I've read comments on this site that red scares people more than blue. I don't know what was ment by the comment.

Do you stick with the color the engine was painted during the time period the car was built? 1967 - red or 1972 block - blue?

Is the blue over red a commonly held belief?

I'd like the forums thoughts on the matter.