Underside Treatment Question

[70challengersix]

Need some advice on what to do here.

I have a numbers matching 1970 440 six pack challenger R/T car and do not have the buildsheet.  The car has been completely dissassembled and is now on a rotisserie.  My paint/body shop is recommending that I put a bedliner material on the bottom of the car because of the durability and maintenance - especially because I mentioned that I planned on driving the car.  The car currently does not have any undercoating - just in the wheel wells.  It appears to have been primed and has the sublime overspray over the primer on the underside.  I believe this is how it came from the factory.

The question is will this non factory undercoating detract from the value of the car down the road if I ever decided to sell. 

[BIGSHCLUNK]

Mine was undercoated when I bought it so I had no choice. I gotta say it cuts down on paint chips from driving. But I would eventually like to "marry" the frame rails, as I have 2 small cracks (typical) forward of the trunk. Could be a pain in the A$$......... 

[farmboy70]

The bed liner coating we use looks very similar to the factory stuff,just a little more glossy.They are right in the durablity.As far as resale that depends on a lot of things. If you are goingto show it in oe type events I would go the factory look. For driving and the 'wow" effect over restored and resale don't get hurt if you paint it completely.
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