Aftermarket bucket seats into a bench seat car- concerns and considerations?

Recaro seats here as well.
These are 11 way adjustable newly recovered out of a 91 BMW 3 series car...

Those seats look great! I have looked at OEM BMW seats as possible donors. Like yours, they usually seem to demand a recovering job...which I don't have the time or skills to do right. I've also looked at old Porsche seats and even Miata seats.

Fabricating the mounts seems a bit complicated.
Is there a thread or another resource on how people have done this? Is there a commonly accepted method?