There WILL be a difference from one car to another no matter what. I went to a local Mopar show and there were three lemon twist yellow cars all lined up and every single one was different. The differences could be in the paint brand or even a tiny error in the mixing process.

When you buy multiple containers of paint your supposed to pour all of them into one container to unify the color before it gets loaded into the paint gun.

FWIW the new base-clear systems never match the original factory paints perfectly either.

Short of having an original sample to compare to there isn't a whole lot you can do. If it looks good to you then go for it. I think that is a fairly rare color so you may never have to worry about it.