Balljoint spacers are old in the IFS world.

They have been used on Toyo's, Isuzu's and Montero (JDM) for years.

The taper is there to keep the balljoint aligned and from pushing outwards. This keeps the alignment in it's stock form.

I'm not an engineer, nor an alignment expert.

These are a direct copy of one's that are sold from shops in the UK and Australia.

I've tried three different one's before settling on these and making a cnc batch.

Google is your friend. Balljoint spacers, montero, delica, pajero, mitsubishi, toyota, etc... will give you all the answer you are looking for.

Like I said before, I got these done because at $150 + shipping from UK or Oz is too expensive for my taste.