That could very well be the case Dan because I also have a decaled Bus with the tow guide base on it that I have owned since new in the stores.
I am having trouble finding the next slanted Label Buses with the later tow guide base and with either the early OR later rear end treatment, so it seems to support Dan's suggestion. Either the decal was revived for a short run while the later base was put on these buses, or as Dan said, a large quantity of decaled bodies were held back in storage until the tow guide base was available for them. Either theory is quite possible.
Right out of the stores brand new Hugh, the Labels came with either a very dark lettering AND border on them, or a much lighter lettering and border printing. The darker labels could be called the "Blue" lettering, while the lightest would fit under a "Gray" description when seen brand new. (Not sunfaded, chemically cleaned, smoker clouded or damaged, etc.)
This fact was true of most of the later original Lesney labels used on ALL of their models right out of the factory. We had discussed some of these color and also some size differences here on the Forum as they pertained to the red #74 Bus labels many years ago now. When you were visiting your favorite stores in the 1960s, all you had to do is open all of each store's stock, and after comparing and examining a hundred or so of each model's labels, you could tell the lightest and the darkest printing of each and buy one of each for your collection along with a few spares of the "Rarer" shade for trading with your fellow snail mail collectors. The blister packs did make it much easier to buy odd models out of big box stores that came without their labels, with reversed labels or with odd colors, etc., because these oddities could all be clearly seen while they were hanging out of their boxes. The next alternative to upsetting all our local store owners for hours was to wait about five years until a very detailed older collection was being sold off in the early 70s. We simply bought these odd color and label shades we may not have seen or could not locate in our own shopping area when the models were brand new.
Forty years later, some odd mint and boxed Lesney collections are still being sold on E Bay, but chances of finding and recognizing these original label color differences by picture is nearly impossible without both models being side by side. At Toy shows we can still find some treasures by comparison, but that is not part of this #66 longwinded label narrative. Pictures?? I'll check my boxed spares for you Hugh......
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