Zinc plating an assembly that has stainless pems

We are inserting stainless pems into CRS sheetmetal and sending the parts out for post plating (electro-zinc deposition. We are not specificaly interested in coating the Stainless... we simple prefer to install the hardware before plating to reduce post plating handling. We are also experiencing significant galling problems (stainless screws). Naturally similar metals gall... My question is this... does the zinc plating have any effect on the stainless. Is some zinc being deposited on the pems?... wouldn't this help reduce the effects of galling?

PEMS do not live well thru the prep steps of plating. They also trap different solutions between the pem and the part, which can cause problems later.
Bite the bullet and install the pem after plate. It can be done quite well with a powered insertion tool. You may have a problem with plate on the thread. If it is, you can chase the thread o plug it during plating. No, you can not plug a pem.