W123 Front Caliper Heat Shield/Piston Position

[serianni1979]

When istalling new pads I noticed that the heat shields on the pistons had deteriorated so I figured I would replace them---wrong...parts can only be had with a purchase of rebuild kit so I figured I would just rebuild the caliper. I have the official repair manual but I am confused about the position of the piston and heat shield. The manual says "the shields should be installed with an elevation on the piston facing upward. This elevation serves for one-sided contact of the break pads while braking which will reduce the tendency to squeal". The manual lists a "tool" to show the correct position of the piston and another tool for the installation of the heat shield and yet another for turning the installed piston so as to correctly position it. Question....is the piston position really that critical and is the use of the heat shields really necessary (Teves/ATE uses heat shields but other models of calipers (Bendix I believe) does not. I am concerned that I will get this job done and have the shields installed incorrectly. Lastly, the dust covers should be installed on the pistons first and then the pistons should be installed, correct? Is there an easy way to fasten the outer edge of the dust seal to the caliper?Thank you in advance for advice given.