My outside temp readout on the dash reads in celcius how do i switch it to farenhiet? Thanks.

you can't.

unless you buy another display module, remove your instrument cluster and swap the displays.

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'94 W124.036 249/040 leder; 8.25x17 EvoIIs
'93 W124.036 199/040 leder; 8.25x17 EvoIIs, up in flames...LITERALLY!
'93 W124.036 481/040 leder; euro delivery; 8.25x17 EvoIIs
'88 R107.048 441/409 leder; Euro lights
'87 W201.034 199/040 leder; Euro lights; EvoII brakes; 8x16 EvoIs - soon: 500E rear brakes
'70 R113.044 050/526; factory alloys; Euro lights

Yup, I've taken apart a W201 module and identified the microprocessor, but there's no indication of any easy jumper or switch location to change the centigrade scale to farenheit. Consider that new LCD modules run about $200, it would be good mental exercise to learn the scale.