2004 Mercedes Benz G500 How to remove old front wheel brake

do you mean
spring steel sheet ?

BRAKE PADS (FIXED BRAKE CALIPER)
Removal & Installation NOTE:Draw off some brake fluid to prevent brake fluid reservoir overflowing when pressing back caliper pistons. Raise and support vehicle. Remove front wheels. Check lining thickness of brake pads and condition of brake discs.

If brake caliper is leaking or dust seal is damaged, replace or overhaul brake caliper.

Remove brake pad contact sensor.
Drive out retaining pins using a suitable drift punch Remove spring steel sheet
Remove brake pads using extractor
Remove contact sensors out of the brake pad. Installation is the reverse of removal. Press brake caliper piston back using resetting device. On 4-piston calipers, secure opposing caliper pistons with a plastic wedge to prevent them from sliding out. Press other caliper pistons back with resetting device. If caliper piston is difficult to move, replace brake calipers. DO NOT bend heat shield in the process. Clean brake pad guide with brake caliper brush . Slightly lubricate brake pads at sides (arrows) with brake pad paste. Drive in retaining pins as far as stop using a suitable drift punch. Ensure that pad retaining plates are seated correctly.

Clean perforations in brake discs.
Check brake fluid in reservoir and correct as necessary. Tighten nuts and bolt to specification. Check fluid level and correct if necessary.
will try to get you some picture if you like

Thank you hope this clear it more for you