Joomla/VirtueMart/E-Check Payment Method

I am using Joomla and Virtuemart. The [login to view URL] payment module that is a part of the VirtueMart installation relies upon bank account information from the user account. That is, the user must provide his or her bank account information at the time of registration. I do not wish to solicit user's banking information before they've decided to make a purchase; nor do I wish to maintain user's bank account information. I would like to alter that payment method so that when a user opts to use [login to view URL] for payment, the information is gathered on a form at checkout, transmitted to [login to view URL] and then deleted. Should be relatively easy. I look forward to your bids.