Never mind; I found it. Sorry!
"…SWSerial position - that is we want GPRS_TX to be connected to D7(RX) and GPRS_RX to D8(TX) "
"…Serial Port jumpers on the GPRS Shield in Xduino position (i.e. Arduino’s RX connected to GPRS_TX and TX of Arduino connected to GPRS_RX)
Still like to know about RTS/CTS support, if anyone has this working. I’ve also found how to enable RTS/CTS through the AT command.