B or RB in A body

I have a 440 in my 70 Dart. Pretty tight, but doable. Tri Y Headers fit good. Spark plugs are easy to change from below. Thinking about building a 383 stroker for it, 438, as I have all the parts, including the pistons. Will up the C Ratio from 7 to 1, to about 11 to 1. Also, the B is about 40 lbs lighter.