Install Fork Air Caps
 

Buy 2 valve stems used for car steel wheels at local parts store.
                                                            
Images show long ones but the short will work perfect.



I used a utility knife and carved away the rubber to the brass center core tube.  I used a small fine file and brown scotch-brite pad to remove any small hard to remove bits of rubber and to make it clean and smooth.
                                         
If you bought the long stems remove the valve core (Shrader valve) and measure where you need to cut the brass tube.  DON'T CUT TOO SHORT or you'll start over.

Now, Prop the front of your Road Star up and remove the fork spring caps.  You will see the top center of the hex has nice machined marks from being turned on a lathe.  There is a defined center point, look closely.  I used a fine center punch on this center point.  Select the correct size drill bit that is the same diameter (or as close as possible) as the brass tube.  Align your hand drill square as best possible or use a drill press and drill the fork spring cap.
                                                         
Test fit the brass tube into the fork cap.  You may want to use a larger drill bit to make a slight chamfer.  Some valve stems have a square bottom shoulder, some have a rounded shoulder like the one in the picture.  
                                       
Remove the brass tube and mix up a SMALL batch of JB Weld.  Use a tooth pick to apply it to the brass tube.  You DON'T need much.  Once the brass tube is inserted into the fork cap I turned the valve stem slowly a couple turns to ensure a complete seal and didn't require a clean-up of excess JB Weld.
                                               
Let dry over night. 
                                                      
Once cured I elected to polish up the whole assembly with Mother's.  I typically use 3 to 5 PSI which I found greatly reduces fork dive under hard braking and gives a nice smooth ride loaded.
                              
2ringstar