hippie ninja

so i have a REALLY old vits spas duet 4 person tub, was passed down to us from my in-laws, and its roughly 22 years old. over the past 12 years i have replaced parts and wiring, to the point of 2020, when i just replaced all of the guts of the spa, new control board, transformer that powers the board, topside controls, pump/heater(uses the pump to heat the water with a heat jacket that goes around the pump), power cord(its 110volt). this would be the third control board that i have had the same area with similar damage, as you can see in the picture, its where the fuse is for the pump.... only thing i can think of is that maybe the power running to my spa may have some damage or oxidation and is causing too much resistance and causing overheating?? any thoughts??

ok folks, i am trying to rebuild the guts of a vita spa duet LD15, and bought new control board, new top side and new pump/motor/heater and wired it all up, and nothing..... need help figuring out what may be wrong.... i get no lights on control board, pretty much the only thing i havent replaced is the power chord, and it doesnt have any signs of damage?? confused....not sure if i have a wiring issue or what, does anyone have a pic of wiring???