[Leica] Help with a flash setup

[abridge at gmail.com (Adam Bridge)]

I know, I know . . . so if you're offended you'll just have to get
over it and move on to another thread. <grin>

I've been asked to shoot a group portrait to match the work of another
photographer shot 10 years ago who is no longer active.

I should have said "no" because it's not my thing but they are my
neighbors and they asked nice.

The setup involves a sofa against a flat white wall. A skylight above
the sofa gives fits to using natural light, and there's not a whole
lot of light in the room as it stands anyway.

When I try to use flash, I have two strobes with umbrellas, I get
shadows on the wall behind the subjects. There's no way to pull them
further away from the wall. The photo I'm attemptng to duplicate has
no obvious shadows.

Can someone suggest a technique - perhaps positioning of the strobes -
to eliminate shadows? I've tried a setup with strobes on either side
(there's not a lot of room for that) Now I'm wondering if I should
have them centered on either side of the camera?

I know - it's all covered in studio photography 101 - but it was an 8
AM class and I slept throught it....

Thanks for any advice you may have to share.

Adam