We own a 2003 American Eagle 43 ft.  MFD I’d # 83742 model E

We are DIY people.

Two of the Coleman Rooftop ac finally gave up the ghost after 15 years.  Old model 47224A879. And we obtained the direct replacement models 47224B879.  (Coleman Mach 8 Plus heat pump ) low profile 15,000 btu energy efficient 

The problem is the new ac metal brackets with screw holes for mounting bolts is too wide apart for the ducted mounting bracket from coach.  The mounting brackets are 9 1/4 in wide and the AC holes are 12 1/4 inch wide.   The plate on the AC is about an inch wide  PL in Houston told us to just drill thru the metal plate on the base of the AC.   The problem with that is the two metal plates on the AC are too wide apart.  ( they run front to back of the coach)  so there is no metal to mount it on.

We just need some advice......any easy solution?  

Donna & Jimmy Blount

Temple, Tx