Two points. One - this isn't the kit that originally cost $15.00. That one was on 1/96 scale, and was three feet long when finished. It was originally issued in 1960. (My source for dates is Dr. Thomas Graham's fascinating book, Remembering Revell Model Kits.) The kit in the picture was originally released in 1970, as part of Revell's "Simplified Series," and sold originally for $5.00 or $6.00. Dr. Graham gives its scale as 1/120, but I have doubts about that. The original, 1960 kit had its maindeck in three pieces, and the deckhouses were built up from individual side and roof parts. The smaller kit has a full-length, one-piece maindeck, with integrally molded deckhouses.
Two - the kit isn't a scale model of the Thermopylae. It's a revised reissue of the "Simplified Cutty Sark." The two ships in reality looked similar from a long way off, but that's the extent of the resemblence.
Whether any of that matters is, of course, for the individual modeler to decide.
Youth, talent, hard work, and enthusiasm are no match for old age and treachery.