A retail installment contract may provide for:

1. (1) any amount of time price differential permitted under Section 345.055, 345.056, 345.057, or 345.058; or
2. (2) any rate of time price differential not exceeding a yield permitted under Section 345.055, 345.056, 345.057, or 345.058.

Acts 1997, 75th Leg., ch. 1008, Sec. 1, eff. Sept. 1, 1997.