Earthquake phd5000 red repair. Need help

Yes, mosfets will be solded on aluminium pads. I will try with low temperature solder. Its very good thing for cooling but a lot more work. Hip is dead. So i am waiting driver chip and hip. I also tryed to power up supply without driver chip, but squere wave look like mess then mosfets are connected. I put only 4 mosfets. I heard that it should work without driver chip.
I was looking for feadback but i dont see.