Just because you're a decent mechanic doesn't mean that you have a degree in welding--nor does it mean that you have a welder available when you're ready to install the O2 sensor on that new EFI system. Here's the solution: New Clamp-On Oxygen Sensor Bungs from Hooker. These are a slam-dunk to install. You're going to drill a 3/4-inch hole in the exhaust pipe, lay the gasket in place, then clamp the sensor bung in place with the included t-bolt clamps. Too easy! And they come in three sizes for a perfect seal on 2.25-inch, 2.5-inch, or 3-inch exhaust tubing.
Not Sure? Review this product documentation before you buy!
Owners Manual
Hooker Clamp-On Oxygen Sensor Bung Installation Instructions.