Ok I learned something new today. I have never looked into the difference in the two motors you referenced.
The first one (you have as 66 style) is 2808767
The second one (you have as 67 style) 2808801
Both my 67s have the 2808767 with a 2-speed switch.
I had two different Valiants both 67s, they had the 2808801 with 2-speed switches.
One of these was a stripped out basic 170, 3-speed manual, the other a 273 auto. Doubt the switch was swapped out on either.
I'm pretty sure both the 2808767 & 2808801 will work with the variable switch.