"Rare" Peugeot Track

Stuck aluminium insert part name here in steel frame:

4 viable options:

1. creeping oil & lots of patience. Then pipe wrench to twist and remove .... or ....
   
2. Vice. Stick post in a big fucking vice and use the frame as a lever to twist post and break the interface between alu post and steel frame.
   
3. Melty melty. Caustic soda that fucking stuck fuck. Be careful please. Wear goggles and don't Tyler Durden yourself.
   
4. Medieval. For those with good work skills. Do not attempt if you have dicks for fingers. Cut off post or stem leaving an inch above the insertion. Insert a loose hacksaw blade into the inside of post and carefully saw outward making sure the cut stays even and you're not ruining your frame. Once cut, either pipe wrench and out or if still stuck. Use big fucking vice to crush weakened post and remove.
   
   

Or a mixture of all of the above.