DIYbanter - Mounting motor and gearbox on old mill...

I have inherited a Brown&Sharp model 0 horizontal mill.

The current arrangement has kind of mounting plate piece mounted on the top
of the mill, where the overarm is clamped. The motor sits on one side of
this "plate", a 4-speed gearbox on the other, and a flat leather drivebelt
goes from the gearbox to the mill's largest pulley. It all looks a bit like
a large "T".

I have to re-arrange everything to fit in a new shop, so was wondering if
there might be a better arrangement. I think the current one might be
top-heavy, and perhaps distort the overarm clamp, and possibly contribute to
chatter.

If I built an angle-iron frame the motor and gearbox could be bolted to
that, the frame to the mounting holes in the mill foot, and I'd get the
added weight holding the mill steady but get it away from the overarm clamp.

Thoughts/experiences/links welcome...