I think you are going to run into the problem that the four-way plug on your truck will not support ELECTRIC BRAKES on your trailer. If it has installed electric brakes then you will want to use them (Actually a DOT Requirement)... Usually if the trailer has a 7-way cable it has electric brakes installed on it.
If the 1007 Trailer does not have electric brakes on it then your adapter down to a 4-way would probably be just fine.
Roy and Carolyn
I claim Horse Creek Country in Southern Ill - Momabear is from North Texas
We live in King George VA
RETIRED DOD DOAF DON CONTRACTOR Electronics Tech 42YRS
"We're burning daylight" - John Wayne
2008 STARCRAFT 14RT OFF-ROAD POPUP with PD9260C and three 85AH 12VDC batteries
2010 F150 FX4 5.4 GAS with 3.73 gears - Super Cab - Towing Package - 2KW Honda EU2000i Gen
K9PHT (since 1957) 146.52Mhz
"We always have a PLAN B"