Slingerland shell interiors, that is . .

I have a couple of 60's vintage Slingerland tom shells that I have acquired in an attempt to get the parts and pieces necessary to build an 8 x 12 tom to add to a vintage kit that I own.

A forum friend recently sold me an 8 x 12 shell w/o badge for $25.

I removed the wrap from this drum and cleaned up the exterior, but the interior was painted white. My limited knowledge of Slingerland drums from this era suggested that these should have been light brown (chocolate milk) colored interiors, so I stripped away several coats of paint and primer and repainted the insides light brown (pretty good match to my other Slinerlands).

Now I have acquired a similar vintage Slingerland tom (9 x 13 - Red Onyx), simply for the lugs and tension rods and . . . lo and behold . . it also has a white painted interior.

Can anyone help me figure out what Slingerland was doing with interior paint back in the 60's and 70's?

I'm really enjoying the resto project, but it seems to me that drums with a natural varnish interior (aka 60's vintage Ludwig's) necessarily required, for obvious reasons, better materials and workmanship and are much easier to deal with relative to restoring these drums.

What do you all think?

I will try to post some pix to give you a better idea of what I'm dealing with.

Thanks.