i recently changed out the plugs and wires in my 95 5.2 and found that the plugs were gapped to .045 and the factory manual says that they should be gapped to .035

i have Jacobs 8.5mm spark plug wires and they allow you to gap an extra .005 so i went in between and gapped mine to .040

does anybody know what is best?

I always go by what the book, or Vehicle Information Label says, which is .035. I do not know if which is best in your case.

I think that the book is the best. But if .045 worked for you, then why change it?