Migrating existing FA pair between grid masters

[#1]

We have a situation where we set up an FA pair on an existing grid, leveraging the framework supported elsewhere in our company. Since then, we have realized we need to run a separate grid on our own and have set one up. Unfortunately, this means that we now have 2 distinct (private, DHCP/DNS) networks on 2 different grids. We'd like to migrate the FA pair to the new grid. There's not a problem with exporting all the data and reimporting it (in fact, I'd probably do that first to make sure the data is populated in the new grid), but we want to have at least minimal (and preferably zero) downtime on DNS (DHCP downtime would be OK), and we want to keep the existing IP addresses on the grid members (since all the clients know what DNS server they use).

IS there any known, tested way to do this? My thought would be to do something like the following:

1. Break the FA pair on "old" grid and sunset one part of the pair (leaving the remaining as the sole member).

2. Bring the single downed device up on the "new" grid, with the same IP address and populate it with the data.

3. Kill the old FA pair (since the new device is up to serve DNS/DHCP), and bring the second device up as the FA partner on the new grid.

Does this work? Anyone ever try it?