This is from Progressive Industries' FAQ page:
"Q: Should a Hardwired EMS be installed before or after the transfer switch?
A: A hardwired EMS should be installed prior to the transfer switch. The reason for this is most RV generators already have built-in voltage and frequency protection. If the EMS is installed after the transfer switch, this leaves the transfer switch vulnerable to power problems."
2011 Rockwood Signature Ultra Lite 8293SS, 12K Equal-i-zer
2016 Ford F-250 XLT SuperCrew, 6.2L, 4x4, 6'9" bed, 3.73
2010 Rockwood Roo 23SS (2012 - 2014)
2009 Ford F-150 XLT SuperCrew, 5.4L, 4x4, 5'6" bed (2012 - 2016)