You need assistance when taking your vehicle through the port at Bandar Abbas. Agents will approach you, but you don't need them - the Customs Authorities do all the paperwork for you. You just have to follow with your wallet and paperwork.
Your vehicle should be offloaded by the local stevedores. However, Bandar Abbas port is small, so I was able to clear customs myself, and then go back through and take the truck into their Customs compound.
Then go to the Valfajre-8 office in town to collect your Delivery Order. Just show your ferry ticket to a taxi driver outside the port, and he'll take you. There is a bank in the Valfajre-8 office, so change some money here for the customs clearance. A few hundred US$ will see you through, leaving spare cash for fuel and food before leaving Bandar Abbas. It's worth changing more than you think you'll need for just clearing customs, as changing money outside Bandar Abbas is not easy. Not that many tourists venture this far, so their foreign money doesn't either.
Go back to the port, go back to the Customs compound to your vehicle, and the guys in the compound will take you to the right office to clear it.
The whole process took about 8 hours. However, I ended up having a free lunch with the Customs guys in their shed, and then spent the evening with them and their mates in Bandar Abbas town. Compare that with the Dubai and Sharjah Customs teams.
Insurance can be found in Bandar Abbas town along the main high street. I'm not certain of the address, but it's on the shore-side of the road, and 20m east from one of the main junctions. There are only a few main junctions, so crawl along the road in an easterly direction, and 20m beyond each junction, look for a doorway leading into a bank-style office with a load of counters.
They don't speak much English, but somebody around should if you need assistance.