How do you tell what liter your Slant 6 is?

When searching NAPA it showed the same part number water pumps for both engines. New One TFW 43025 and Remanufactured one WP 58177

Casting Number Size Year Engine Family
2202843 170 G
2205630 170 G
2463395 170 G
2264478 170 G
2463230 170 1965 G
— 198 G
2202857 225 RG
2205528 225 RG
2463430 225 1966 RG
2806830 225 1968-70 RG
3462605 225 1975 RG
2951694 225 RG