how to fill / fix pitted steel before plating tin/zinc??

[MrHeaterbox]

I have some old auto parts that I need to plate with bright zinc (tin/zinc). After bead blasting, the parts still show some pitting. I know that the electroplating process is not going to fill these pits in, if anything, it will make them more obvious. Is there a metal filler compound that I can use before plating to make the part perfectly smooth that will plate out in the bath to make the part look as good as new

Someone told me you could use Evercoat's Metal to Metal body fill on the part to fix light pitting and that it will accept tin/zinc plating just fine.

Thanks in advance for your help! BRENT