well, I was planning to start on a crosshatch anyway, so I'll just start in a corner. An hour and a half to prepare for 2 golems and a H/K is more than enough if you're playing with Spirecraft. Rams protected by cloacker starships should be able to do the trick.
What happens if you destroy all train stations in a galaxy? Will trains no longer spawn? Will trains just move randomly instead of moving back and forth from stations? Or will trains cease to move at all?