I can't remember off the top of my head what was written in the manual, but try to keep it below 150kmh, 4000rpm, C mode only for the first 2000/3000 miles, but vary the RPM range as much as you can. Then slowly bring it up to the maximum RPM range and speed as you go up from there.
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New car: 2004 SLK 55 AMG, Iridium silver.
Additional: Chrome door lock pins, K&N Performance Filters, Piecha roof control module
Sold: 1998 SLK 230K, Linarite blue.
Brabus: Front spoiler, side skirts, rear apron, exhaust, gear shift + hand brake, 17" Monoblock IV, hubcaps/wheel locks, Aluminium doorlock pins, polished safety roll bars, Brabus logo
Digit-Power: 30bhp + 50nm torque
Additional: Chrome side indicator frames, Chrome SRS badges, CLK grill, Lorinser Wing, Rieger headlight covers