This is kind of a niche item :)
In the instructions, Powerflex explicitly mention : “Ensure that suitable adapters or pressing tools are used and that any force is applied to the bush face and not on the bonded metal bracket.” → https://www.powerflex.co.uk/i/product_images/19-1917%20FI%20min3.pdf
Many youtube video recommend to insert the central part by making lever with a metal rod (or a screwdriver) inserted in the opposite hole of the metal insert.
https://youtu.be/gQ6TP8vWals?list=PLeuwCwZXwev0-HDWhVCNAWfS4Ps3jNrdQ&t=2040
This design transmits the force applied to the metal insert directly to the bush face. In this way, it reduces the risk of tearing off the metal plate if it is levered into place (see the pictures).
To hold the 2 bodies together, use an M6 bolt.
There are 2 designs, one shorter than the other. The bushes were not in the exact same position on the metal insert.
Fusion 360 file provided. If you need some changes, feel free to contact me.
The author marked this model as their own original creation.