So my brother in law who restores old Mustangs reacted all shocked when I told him about the van conversion and he found out that I hadn't put an undercoat underneath the NV. I didn't even know that was a thing... He is trying to convince me that I need to undercoat the van asap to prevent rust especially since they salt the roads here in Tahoe. Any thoughts? Is it really necessary? Being from Germany where roads are salted and wet for many many months and the climate is quite wet I haven't heard of anyone with a new(er) car having rust issues. I thought that was a thing of the past. So, is he just being paranoid based on his work with old rusted-through Mustangs or should I consider an undercoat? Thanks!