The seven bearing 170 crank was rare, so most 170's will be four bearing in the US. Ford US did some seven bearing specials, but 99 out 100 170's will be four bearing... I think 1972 was the last year the US 170.
Down here, everything after 1964 got seven main bearings.
The 2.5 to 2.94" stroke difference is taken care of by the one size fits 4.855" rods and 1.738" tall pistons in the 144.
The 170 has the really common 200 size 4.715" conrod, and 1.618" piston in the 170.
the info I use differs a liitle from Classic Inlines historicals, I'm sure 7.803" is the bluue printed 0 deck, and that 1.531 and 4.715 are right for a stock 7.830 . But 1.511 is 25 thou down a 7.808" deck block. Take my readings with a grain of salt, but that's bassically what they are.