Fifth wheel height

Look under the plate ... how many inches down to the frame rail...?

 

If you do not have steel lift tubes under 5th wheel slider for like a tanker needs that you can take off, then a trip to the truck junk/yard to find lowest stands they have, If your 5th wheel plate has no slop in it then you can just buy or trade in your hi stands for the lowest you can find,4in is a lot to lose you will not have much rocking in the 5th wheel at all with that low stand?

 

To get to 48 it will likely take a combination of lower fifth wheel/riser and Low profile drive tires.What size are the drives? Check ride height and set to bottom of window.

Remember if you change drive tire size youll need to calibrate the speedo.

 

Pictures of your current 5th wheel might help.

 

Those risers look REALLY tall... Id be willing to bet that just changing the risers will get you 3 inches.

 

Holland makes a low-profile mount. The ram is in front of the fifth wheel. Valley Truck Parts in Michigan sells them. Pretty straight forward switch.

 

Do as @Bean Jr. says.
It could be that if you do that you don't need to change the tires .
You will need to get measurements to be shure.