You should discuss your church bylaws with a lawyer if you have 1840s-style “trustees.”
Some church constitutions name “trustees.” Few remember why they have them, other than to sign legal documents if the church tells them to do it.
In most cases, they’re not necessary. Trustees were a clever way to solve a legal problem back in the ’40s — the 1840s. Unincorporated associations can’t own property in the name of the church, so associations appointed “trustees” to hold the church property in “trust” for the worshipers at that place.
Unincorporated associations still can’t hold property in Missouri, but corporations can. Missouri allowed church corporations to own property in their own name, starting in 1851. Your corporation will have to name “directors,” but church “trustees” rarely operate as “directors.” If you church has a governing office — whether it be a bishop, elders, or deacons — the trustee could be an extra, and confusing, layer of leadership. Obviously, if your documents are based on the legal rules of the 1840s, you may want to consult with an attorney about an update.