We have run Taylo Spiro pros for 440s for years.Mine has 2 inch TTIS my kids 413 had 2 1/8 tubes.Last set on mine were like 15 years old or older just looked tacky.Only wire thats close is 7 and Irun a heat boot on it.We run holders fro Summit that bolt to lower VC bolts and hold wires up and away.When you take the lower bolts out the entire holder comes off with wires attached.Been on close to 20 years.Rocky