158 acres is possible and would not be uncommon in areas held by old Clinton leases in Ohio. Many of these old leases limited unit size to 160 acres. At the time that was 4 times the minimum of 40 acres. I am in western Carroll county and have property in two horizontal units, Cairn 5H and Morsheiser 5H. One unit is roughly 158 acres and the other roughly 153 acres. The units are roughly 1100ft wide with a 5325ft lateral and 1050ft wide with a 5450ft lateral. You can find plats filed on line at the ODNR website.