(1) The contracting agency or any national bank, state bank, trust company, or safe deposit company located in the state of Montana, designated by the contractor to serve as custodian for the obligations pursuant to 18-1-302, shall collect all interest or income when due on the obligations so deposited and shall pay the same, when and as collected, to the contractor who deposited the obligation.
(2) If deposited in the form of coupon bonds, the contracting agency or the designated custodian, pursuant to 18-1-302, shall deliver each such coupon as it matures to the contractor.