Paint protection film - small spots still need float chemical?

Oct 17, 2014
SW Ontario Canada
On my QX60 there are 2 very small areas on the bottom inside lip of the 2 left side doors that rub against the weatherstripping. The weatherstripping is abrading the paint off the metal of the doors. I touch up the spots, and within 2 days the bare metal is back.

I got a piece of 3M paint protection film, it's 4" x 24". The spots that I want to protect are only 0.25" x 0.25" , so I plan to cut some squares of this 3M stuff to allow a bit of overlap to the good paint.

Today I applied my base coat paint, left the doors ajar and will let it harden all weekend in garage.

My question: the 3M PPF instructions says to make my Distilled Water, IPA 70% and J&J baby shampoo mixture to apply the film. Is this really necessary ? The 3M film is sticky when the backing is removed, and I don't exactly have a big area to apply to... so can I just peel and apply? or am I fooling myself?

Appreciate your input.