early 273 pistons.

I looked at your link and the 1.822" dimension is for what is called "Maximum Compression Distance". That works out to be deck height above pin center for the standard rod, crank and block dimensions, but I don't think that is meant to be actual piston compression height. The 318's were way short of that and the 340's longer, yet they list that number for all LA's so that is not actual piston CH.