When usng mausoleum of the emperor?

u can activate this card pretty much anytime u have a monster that has a high level and u can pay in multiples of 1000 to summon a monster without tributing so like dark magician girl would be 1000 life points u have to pay now that being said can you use spell economics which is a continuous spell nd says you do not have to pay any life points to activate a spell card so would that work with the field card above because it activates when u want to summon a powerful monster by paying life points and spell economics makes it where i dont correct or would that not work?