Several of us A type owners ( I have an RV-7A) have had to replace or repair a cracked step. I have had the experience and I think I have figured out the easiest way to remove and replace the step. You don’t have to drill off any panels. Get out your plans and determine where the inner block is under the baggage floor and cut an oval shaped hole over it and remove the bolt. Next drill out the rivets holding the step out and pull the step straight out. You can remove the screwed on panel over the flap pushrod so you can vacuum out the River pieces. Repair or replace the step. It is easier to repair and reuse your old step of it can be repaired. Match drilling a new one would be challenging. If the crack does not extend around to the front side of the step, it should be possible to repair it. Van’s sells the repair gusset. I sent mine to the guy who builds the steps for Van. I wish I could remember his name. Quick turnaround. Anyway, pop rivet the new or repaired step in and make an oval shaped hole cover and pop it in over the hole in the floor.