How can we delete transactions in the bank feeds and does anyone have detailed set up instructions?

We are new to using Acumatica and unfortunately, we are having difficulty setting up the bank feeds to pull in correctly.  Our initial direction was to pull them in BEFORE rules were set up to identify the card users, so they all pulled in under one user.  We have not been able to obtain clear step-by-step instructions for the proper set up of credit cards.  We have fully utilized all of the on-line tools within Acumatica and Acumatica University, but they are lacking the details we need to get the system set up properly.  We would like to delete all of the bank feed transactions and re-pull them now that we have rules set up for pulling the credit card users. So, first question is, does anyone know how to do that?  Second question: does anyone have a step-by-step set up guide they would be willing to share to help us get this set up?