Shipping info not billing, being sent to PayPal Payments Standard 2.0 Gateway

I have the “forms sent to gateway” settings correct, to point to the ‘billing’ fields in the form, but the shipping fields are being sent instead.

If I turn the “send shipping details” option to “no”, it doesn’t pass any info through at all, forcing the purchaser to re-enter their info again on the PayPal screen.

How might I send the billing info to PayPal?

https://www.ads-software.com/plugins/wp-e-commerce/