Crossing from Namibia to Zambia overland in own vehicle

Hi! I am moving to Lusaka from Ireland in a few weeks time. I am shipping a jeep to Walvis Bay where I will collect it and drive it up to Lusaka. My first time doing this self drive so any information about getting a vehicle through borders gladly appreciated. Also any info on how to pay customs/import taxes? Took a bus from Windhoek to Lusaka last year so was going to take the same route up the Caprivi strip. Anyone think I would be better going through Botswana for any reason? Any tips at all? Thanks a million.