OK, when two panels get put back together...what can be used to prevent rusting between the seams and still be capable of taking a spot weld?????

 

weld-thru primer. should be able to get it just about anywhere

 

Would I not use any caulk or such? Is it not necessary for that?
We will be reinstalling the cowl soon, I POR-15'ed both parts of the cowl and I'm wondering if I can zap it back together with the POR-15 in the seams and it still hold up or if I will have to use something like this weld through primer?