When I did mine recently the screws were rusted solid and just about all of them snapped off which was not a problem as it would allow the V bars to slide out of the frame except for one thing, the bars were rusted to the sheet metal of the frame. Days of soaking with PB blaster did not help. To seperate these I had to apply heat with my acetelene torch using the brazing tip until the sheet metal just glowed red but did not burn though and then pull the old rusted V bars out of the frame. New bars are available so don't worry about them it's the frame that's high $$$ if you damage it. Good luck!
