Apologies on the whole Merrimac/ Virginia thing. My use of the name "Merrimac" was in reference to the actual title of the book I read in the 5th or 6th grade. The CSS Virginia certainly deserves her own name in recognition of what an advanced vessel she was. But in the early 1960s it just wasn't used, except in the sentence "The Confederates renamed the USS Merrimac the CSS Virginia." Monitor and Merrimac has better alliteration too.
I built those models too. they were both light grey. I believe they were both lost in the great battle of the Kidney Shaped Sea. BB guns, cherry bombs and clorinated water devastated many a warship that day. The only casualty on our side was the swimming pool filter pump. It died of plastic inhalation.