You can buy resistance wire in rolls. I'm don't think it's worth the bother though. I have 50 feet of it here.
1020 has a Delco starter that already has a built-in resistor bypass marked "R.". Just buy a stand-alone resistor and wire it in.
The OEM coil on the 1020 has 2.6 ohms on the primary. Just wire in a 1.6 ohm resistor and you'll be fine. # ICR11 at NAPA. Or buy a new coil that does not require any external resistor like a NAPA IC-14 (3.25 ohms on the primary) for the high-price Echlin coil (made in Mexico), or the NAPA MPE IC-14SB for the same in the much lower priced Chinese version. My tractor works just as well with Chinese volts as it does with Mexican volts.