Help ID motor. Potentially/likely canadian

A56 said
according to this the head is a 75-80
1975-80 225
3.7
3.40
L-6 Crank Centering Ring
2.157", Mech. Lifters 2806830 2463430 4027600-5 3698447-1 4104362

So
3.7,
3.40
2.157"
And all those other numbers....
What do these mean?!

Also thank you for this! Not sure how you got all that info.