About a year ago, someone in Alabama? made some lower spindle bolt repair inserts. I have a set of them and would like to correspond with that person regarding the proper procedure for drilling and retapping the lower threaded hole. Does anyone know who made these inserts?
You can install a helicoil. The trick is top line up the drill and the tap so they coincide with the original kingbolt centerline. Sometimes the hole is worn oversize such that all you have to do is tap it and install your helicoil.
You will likely have to install the helicoil from the bottom and trim the tang so you can screw the bolt in. Have 2 or 3 helicoils on hand as you can mess them up as you install them.
You will have to tap it from the bottom also.
You can tap it from the top, but you need to make a tap driver that pilots in the upper hole. Same for drilling it before heli-coil tapping. This will ensure good alignment.
Also, notice that the first few threads are omitted in the top of the lower hole. If you install the heli-coil the entire length of the hole, the kingpin will not screw in far enough and leave a gap under its head.
The best way to do it is to use an original Stevens front axle repair tool like Dan Hatch has. They are around. There was one on ebay last week.
The best way to fix a bad front axle is to throw is in the iron pile and install a good front axle. I have given away many, many front axles and will still do so with any purchase of something else.