Mirroring and welding re-topology?

[system]

Hello,

Amidst the process of retopologizing a high poly model I found out
that I forgot to turn symmetry on so I have only a half. :o

Instead of starting anew is there a way to mirror my half and merge
the two so that I still can use projection for the underlying details and
do more retopologizing?

Thank you

[pimeto]

Export your low poly mesh that you created to your 3dapp, fix it, mirror it, then import it and project your details.

[system]

That is of course also a possibility claps forehead

Thank you