How do you adjust ignition timing on 1995 ford bronco 5.8?

If it has a distributor, there is a bolt near where the distributor shaft enters the engine. Loosen it. Use a timing light gun, it connects to the number 1 cylinder spark plug wire and shoots a light. Aim that light on the harmonic balancer while the engine runs. There should be a little metal/plastic tab with degree markings on it. When the light shines, you should see a mark (usually a groove) on the harmonic balancer right in the range of that metal/plastic tab. Rotate the distributor to make that mark/groove line up with the right timing degree.

Dont have a timing light gun and dont want to buy one, do it by ear...with just slight movements of the distributor, you can hear when the engine is running its best. Won't be perfect, but will be close enough.

If it has coil packs and is electronically controlled, you can probably just reset the computer (disconnect the battery and leave it till the next day).