As a rough rule of thumb
the most effective way to increase combustion chamber volume to decrease detonation
is to remove from the exhaust valve side.

On the exhaust side
for performance engines
'de-shrouding'
the exhaust valve surroundings
will increase high lift exhaust flow.

If there is a 'bump' around the sparkplug hole
that looks odd to the casual eye
I would not remove any of that bump
until I had thoroughly researched it.
An odd shape around the sparkplug may be either for increasing turbulence
or
for protecting the sparkplug gap initial spark from being 'blown out'

For example
it is worth looking at the bump around the sparkplug hole of the
stock 1992 Magnum,
RT Magnum and
aluminum Viper combustion chambers.

To my eye
there were subtle changes
that may have been refinements
to 'high swirl'
fast burning performance.

It is also worth asking yourself:

as Squish pushes out a
'tidal wave'
or turbulent gas from either side
where will it mostly head toward,
and will it increase or decrease
clockwise or counterclockwise
spin of the gases?