Hi,
I've been through a tar nightmare in my car a few times

The mini rear is a vortex that attracts dirt, and if tar is on the road it is a nightmare

The worst was after I did the MT Buller sprint when the road virtually melted
From experience, trial and error, and advice from detailing and motorsport people, I can offer advice as to the best way to remove the tar specks
Use a soft sponge and kerosene. Soak the sponge in kerosene and gently rub onto a small affected area. The tar will gradually dissolve over 1-2 minutes. Then use copious detergent and water to wash of the liquefied tar and kero. Repeat this process on all affected areas. It is suprisingly quick, and will take you around 30 minutes to have paint surface that is smooth as a babies bottom

The technique also works on wheels.
The key is to be patient. Don't try and rub the tar off, otherwise it scratches

Be patient and it will gradually dissolve.
Make sure you thoroughly wash off all residue when you are finished.
Cheers
Robbo