We had passed Lao Customs the day before to get into the border economic zone. Customs took the cars papers. On exiting Lao Immigration they wanted the same papers and after an hour and a few phone calls to China, Lao Immigration, who were genuinely trying to solve the problem (their computer needed some numbers), accepted the figures from our car registration papers.
Over the hill to China and a huge Immigration and Customs centre. Electronic form filling and buttons on the immigration desk to give feed back on the performance of the service provider. It took 10 minutes including the cars. Having our Chinese guide, Andy, I am sure expedited the whole process. We motored the 25 km to Meng-La, visited the Traffic Police, had the cars inspected and were issued with our Chinese driving licences. The vintage cars got their tyres kicked, the Cruiser got a brake test and tyres kicked, and were given temporary Chinese plates. We had finished the process by lunch time so could all go next door for lunch and get to know Andy.