Now power to engine/lights/horn battery is good

Coach Breaker Panel" fuse

HERES THE ODD PART: WAS TRACING THE CABLES FROM BATTERY AND TRACED THEM INTO THE BOX MARKED "BATTERY MODE SOLENOID AND DISCONNECT RELAY LOCATED IN SIDE HERE"
Opened that box up and when I would hit try and reset the
"Coach Breaker Panel" fuse... I could at times get the lights , horn , and even ignition to turn on. But when I would try to turn the key to the start position... wasnt enough power.

i think you already answered your own question bad disconnect solenoid. go to a auto store an get a 12v test light or a volt meter and see where the power stops one lead to ground=(frame)the other lead to each connection in the power path see where it quits. these work great12v test light if you can get it to light the head lights leave them on and turn the key if they go out you have a bad connection,"Coach Breaker Panel fuse",solenoid,or battery. what battery are you looking at coach battery or engine starting battery?