Hello I`m from Holland !!

Welcome to FABO from SoCal. You're going to have fun here!
Lots of information available about big-block swaps into A-bodies and lots of members here have done it. What rearend does your Dart have? Better be at least an 8.75. Your 440 will scatter anything smaller.
Suggest you also look at further suspension upgrades to handle the heavier weight of the big block.