PM sent as I am not sure the Archive & Library Officer wants their direct email published ... otherwise the starting point can be the web site email found here:
http://www.tankmuseum.org/schools-and-research/archives
Rego number, i.e. 03 CC 29. Costs are currently GBP 25.00 by PayPal, the two Ferret cards and DVLA letter can be returned as electronic scans, or original DVLA letter with photocopies of cards by post if requested.