[Permanent improvement and interest and retirement

funds.] The proceeds from the sale of said bonds shall be paid to the secretary and treasurer of said regents, and shall be placed in a separate fund to be known as "permanent improvement fund" to be used and paid out only for the specified purposes enumerated in this act [21-11-15, 21-11-16, 21-11-18 to 21-11-26 NMSA 1978] and upon order of the board of regents, on checks signed by the president or vice president and by the secretary or treasurer of said board. Provided, however, that moneys received on account of accrued interest on said bonds to date of delivery shall be placed in the "interest and retirement fund" for the liquidation of said bonds as hereinafter provided. The cost of preparing, advertising and selling said bonds, including any necessary legal expenses thereon, shall be paid out of the proceeds of the sale of said bonds.