I know that weld thru primer is heavy in zinc...Since the Cold Galv paint is also heavy in zinc can it work as well....I'm at work for a few days and can't get to the store but I do have the Cold Galv.

Thanks

If you are welding in new panels then weld thru primer is the correct application.
The wtp will coat areas such as inside flange area's and lap welds that are otherwise inaccesible post weld. WTP also allows burnthrough at a welded joint or seam. Corrosion protection still needs to be applied after a repair or panel replacement. This would include primer, epoxy primer and seam sealers and caulking. Wtp's are still in dispute on the Hot Rod sites.

If you are looking for a coating with anti corrosion properties in a non welded or simple repaired area I would use a primer if already top coated, epoxy primer if coating over bare metal.

Zinc rich coatings do not have good adhesion properties and tend to not hold up well by itself. They are also not good to apply as a base coat under other coatings as a primer should. Zinc coatings by themself will usually peel,lift or degrade if left to the elements.

What are you trying to coat?