OP
200-300 wpc, 40lbs, SS, not Class D
Mono-blocks will divide the gross weight, but, it’s a near impossible ask.
That is why I said: sell those speakers (the source of the extra weight needed), get efficient speakers (which get moved once) and need much less power (smaller/lighter/less heat/less cost/more placement options).
that's why I called it a 'lifetime solution'. we get older, back/knees/shoulders fall apart.
Efficient enough, you could then try tubes. Mono-blocks probably to reduce weight.