https://www.msdignition.com/products/2-step_and_rpm_control/modules_and_accessories/parts/87451
MSD 87451 MSD RPM Modules - 5000 Series Kit - Odd Increments
Each kit is within a 1,000 rpm range. For example, the PN 8745 is supplied with: 5,000, 5,200, 5,400, 5,600, 5,800 modules.
msdrpmmodulesserieskit