Well the big ones came out nicely on the hydraulic press
...so long as there's a bit of penetrating oil.
Because the edges of the subframe were a bit in danger - a bit on the edge - on the frame of the press I didn't exceed one metric ton on the gauge.
This trick didn't work on the small bushings - the BMX stunt pegs I was using as pushing pieces just went straight through the rubber part pushing the aluminium insert all the way through => doh!
Different solution will be made shortly...