It's easy - just a stamp, although doing anything much with your car in Singapore without a whatsit pass thingy doodah is a pain, so if you were planning to spend the day in Singapore don't drive into any carparks because you won't be able to pay (voice of bitter experience... ended up parking on the street and taking a taxi to where I wanted to go)
DHs employers have cocked up our dependent's visa it seems. In order to stay legally, she and I need to leave and get another 90 dayer and hope they sort it out later. I wondered how easy it was to drive across the causeway and get a stamp? Advice please. We are considering doing it on Sunday. DH can share the driving then.