@sherburn2LA....I presume you're talking of in-flight refuelling, in which case the 'elf 'n safety jobsworths are more important than W&B.
Firstly, you'd need a written risk assessment, then approved safety-harness,hard-hat and high-vis vest. Your footwear would have to be antistatic and, of course,your mandatory safety-tether would need to carry a proof-loading certification.
If your aircraft is of high-wing design, you'll need to work on your methodology for gaining access to the upper surface (approved step-ladder with appropriate hooks? )
Nearly forgot the goggles, respirator and gloves needed when pouring a volatile,toxic liquid in a windy area.
