We had our 4x4 shipped to Singapore from India in 2009. We were also informed about this letter, autopass (you need to make arrangements for toll in advance) and were told to get insurance before we could leave the port.
We decided to try our luck first and drove to the exit of the port. We just handed over our CdP for a stamp, which they gave us within 5 minutes, they openend the boom and off we went
This was probably the easiest import ever during our 3 year trip! But we must have been extremely lucky there. You could try though. If they won't let you go, you can probably park your bike and grab a cab to arrange things with the AA.
We had a very helpful agent who allowed us to unload our Landy ourselves to cut costs. They were very straightforward.
Name of agent:
RONG DE DISTRIBUTION PTE LTD
Tel: (65) 6223 1833
Fax: (65) 6720 1683
Website : WELCOME TO RONG DE GROUP OF COMPANIES
We were helped by a guy called Dave (firstname.lastname@example.org) not sure if he's still working there. Their handling fee was very reasonable.
Let me know when you are around KL and fancy a