early items: grapple beam before boost ball
In Hydrodynamo Station, use an underwater dash to reach the light door as if you were doing early gravity boost. Go through the next room and you'll end up in Gathering Hall. Use the bomb slot here and enter the portal.
Ghetto jump off the side of the spinner and land on the center of the laser emitter. The spot you can stand on is quite small; you'll slide off if your landing isn't precise. From the laser, just space jump to the light door at the top.