I had an old machine like yours that I picked up used and came with out a manual. I called Blum and gave them the serial # and was asked where the power switch was located, it was in the front like yours, I was told that the machine was unsafe. Apparently Blum had gone around the shops and retrofitted safety upgrades but was no longer doing this, instead would exchange my old machine with a new one. They had someone drive from N. Carolina to my shop in S.E. Pa., pick up machine, drive back to N. Carolina to inspect machine and than back to my shop with new machine in one day.
What a great company, like Festool they stand behind their products!
David