CENTER TO CENTER ON STUDS. SHORT LEAD TIME ON THIS KIT. Feel free to ask us about conversion kits for almost anything including trucks, cars, generators, tractors, boats, motorcycles, RVs etc. We can build a kit to convert almost any engine! This product can expose you to chemicals including l. Ead and lead compounds. To the state of California. These products contain a chemical known to the state of California to cause cancer and birth defects or reproductive harm.