I have an 87 Ranger and it is welded on.
What have you welded ?
Air fuel ratio gauges rely on a sensor that is very much like an O2 sensor used in a car's emmission system. Therefore you would have to have 'bung' drilled and welded into your cars exhaust system to mount the sensor for the air/fuel gauge. After that, run the wiring and mount the gauge like any other aftermarket gauge.
Yes, you can pipe them into one. Why would you want to?
There might be rules and laws involved in this, but generally when a pipe gets a hole in it corrosion is the reason and a replacement is cheaper and the correct way to do it. If the pipe had some mechanical damage like driving over a sharp object a weld repair is possible and can work fine. Nothing lasts forever.
It is usually not the weld but the metal right beside the the weld. If a piece of metal needs to be welded, it may be getting thin in other places and when it is welded, the heat from the weld can weaken the metal and in some cases cause the metal to crystallize and be more brittle than it was.
They are welded in to the exhaust stream so as to prevent easy removal, its a government thing for the protection of our air quality.
The chasis is usually both bolted and welded and even riveted in the trucks.
welded on
bolted in from new
Yes on the exhaust manifolds but the cat should either be welded or bolted on after your Y pipe then goes to your cat!
Bolted on
because it is
Its welded.
They are bolted on
they are usually bolted on in the front of the converter.
It's bolted on the body, welded on the door. Door pin/bushing replacement guide: http://www.digitalrevo.com/jeep/doorpins.html
Direct replacements are bolted in and some aftermarkets are welded in.