UPDATE March 2012: see post #3 below re changes to this procedure
Complete your temporary import forms online before you leave home
You are allowed to temporarily import a car, 4WD, motorhome or motorbike into Morocco for up to six months per calendar year. Commercial vehicles are limited to three months. In order to take advantage of this scheme you need to complete a declaration of temporary importation form (D16TER). This is normally a three-part no-carbon-required form with a green copy, yellow copy and white copy.
However, several years ago on the Morocco/Mauritania border I saw details of a web-based system you can use to complete your temporary import form (D16TER) for Morocco online, then print it off for handing over when you get there. This saves having to find out which window you need to queue at for the form and means you don't have the hassle of working out how to complete it when all you really want to do is get through the border and ride!
Go to Moroccan Customs website and complete the form as follows:
Prénom and Nom: Your given name and family name as they appear in your passport (in capitals)
Identifiant: If you have been to Morocco before you will have a police number in your passport in the format 999999AA, in which case click on Étrangers non résident (non-resident foreigners) and stick the number in the box. If you haven't been to Morocco before, click on 'autres'.
Immatriculation: your registration number/licence plate number (no spaces)
Marque: Manufacturer of vehicle (BMW or whatever). If yours isn't listed, click on 'autres' which will bring up a dialog box to type into.
Type: Model of vehicle (1200GSA or whatever) as shown in your vehicle papers
Genre: Choose from pull-down list box--motorbike, car...
Pays: Your country of residence
Date de 1ere mise: date the vehicle was first registered in the format dd/mm/yyyy
Chassis no: your VIN (vehicle identity number from V5C).
Press 'Imprimer' to display the data in a formatted manner as shown below.
Now print the resulting webpage. You get three copies printed out, the equivalent of the green, yellow and white NCR forms. Two of the copies fit on one A4 page, the third copy on a second A4 page. Use portait format not landscape, and if you are using US letter format paper, adjust the margins so it will print all the details.
NOW SIGN ALL THREE PARTS where it reads 'Signature du déclarant'
PS: Firefox and some other web browsers may not work correctly, so use Internet Explorer if necessary.
The third copy (on the second A4 page) is the one retained by the customs at the port of entry—Exemplaire service 1 (Entrée). You then go on your way with parts one and two on the first A4 page. When you exit Morocco they tear this page in half, you get to keep the top part—Exemplaire déclarant—and the exit customs retain the bottom part—Exemplaire service 2 (Apurement)—for audit.