Best way to use only one order number (and no other number) with 1.5.6.1?

[madmartian]

I have been using an order number for 10+ years in my old cart and would like to continue using an order number. I hate the reference number in PrestaShop. I have searched and found many different solutions, but I am confused about what works for my specific situation and for 1.5.6.1 - most of the threads are pretty old. So for today, what is the best way to use one normal, sequential, order number for every order and never see that ugly reference number? I don't want multiple numbers, like reference numbers, delivery numbers, and invoice numbers.

 

In summary:

1. Order number only - no reference or invoice or delivery number (or make them all match).

2. Sequential.

3. Start numbering from 5000.

4. No other numbers - just one number refers to each order for both customer and store owner.

 

What do I need to do to make this happen in 1.5.6.1?