The throttle bodies may require more than just boring out the housing and making a new blade. While the shaft is modified, many of these units have excessive endplay which is due to the aluminum housing being worn. The repair is making a bushing to address that. Furthermore, the original throttle shaft seals are no longer made. Gbodyparts and other vendors offer a repo but the OD of the seal is too large. So again one would need to open up the housing to repair. I've done a few of these, they all required a different repair.