How to disable High Availability?

Go to AskF5.com and look for SOL10228: Converting a failover unit to a standalone unit, or use this URL:

http://support.f5.com/kb/en-us/solutions/public/10000/200/sol10228.html?sr=38792569

I believe in v10.x there is an option under System | Platform that specifies whether a unit is part of a redundant pair or standalone. I would:

1. verify no vlan/gateway failsafe or HA groups are configured (remove if configured) - System | High Availability
2. disconnect all cables on standby unit aside from management interface (including failover cable, at which point units will go active/active)
3. change each unit to "standalone" - System | Platform
4. validate that no network failover configuration remains - System | High Availability | Network Failover
5. power-off and move unit 2 to other DC

Hopefully they won't remain separated for too long, Murphy's Law being what it is...

Awesome Shaggy, your solution looks to have merit and thanks! And yes, it's temporary just to move everything, we just need a landing zone to move everything as seamlessly as possible and re-pair them once the move is complete.

Do you know if the secondary will keep its config or will it default to "hey please set me up" again?

It should keep its config. Also, if you do any connection mirroring for virtual servers, disable it while the boxes are split.