Accounting sequences - Same number for SLA and GL?

Hello.

We have a requirement to generate a sequence number for the Subledger Accounting and GL at the same time (same number).

The user wants that a sequence number gets created on SLA for some modules, say AP, when they create accounting. And that sequence number to "get transfered" to GL...when the accounting entries are transferred to GL.

Is that possible?

I thought we could achieve this using Accounting Sequences, but we just see one field for Sequence Entity and also just one for Sequence event, per Sequencing Context.

Please advice.

Thanks in advance.

Enrique.