3 5/8 is still larger than your needed size and can still square it up. Just take a little from one side, flip and square to size needed. If you are still testing, the rests of your blocks you can cut a little bigger to give you more wiggle room. And, I make 4P the same way but others might pipe in with a different technique.
I always substitute easier sewing techniques than offered in patterns. That's the quilter is us!