Perhaps you have the wrong bar. This is what the Tech Section says about sway bar options...
Sway Bar Options For Your Ford Ranger
Looking to add or upgrade the sway bar on your Ford Ranger?
Front Bars:
If your Ford Ranger didn’t come with a front sway bar, you have an option of adding a factory one, if you can find one in a salvage yard (or craigslist).
- 1983-1988 are interchangeable,
- 1989-1997 are interchangeable
- 1998-2011 are interchangeable
Bars can be swapped between Bronco II’s, Explorers, and Rangers of the same year range. The exception is the 95+ Explorers that switched to the SLA suspension. The SLA Explorers will only interchange with SLA Rangers.
There were (2) different mounting setups for the front sway bars:
Behind The Front Axle:
This setup mounted the sway bar to the inside of the radius arm, and was attached to a crossmember that went between the radius arm brackets.
There's more to read. Here's the URL
https://www.therangerstation.com/tech/sway-bar-options-for-your-ford-ranger/