Discount Coupon Equal to Shipping

I am using eCart 5.03. I have created a shopping cart for a client that is working great. The shipping cost is supplied by UPS automatically. My client wants customers who pick up the product in person at their store not to pay the shipping charges when checking out online.

How can I use the coupon feature of eCart to automatically generate a discount equal to the shipping charges? The shipping charges are not entered into the checkout process until after the customer completes the shipping information.

Any help will be greatly appreciated.

Thanks
Vince

follow the "Creating a Coupon system for your eCart store" tutorial from the Archived documentation section of the eCart support page:
ecart/


when creating the discount, set the calculation to use a flat rate, and enter the following for the flat rate:

$this->GetShipping();