narrowing ball joint beam

i have lowered my 68 semi auto beetle with ball joint front end on drop spindles
the tyres are rubbing on turning despite having the offset of the wheels altered
the next step is to narrow the beam and add adjusters

can anyone help with how many inches /mm to narrow the beam to prevent tyre rub - stock wheels with 165 tyres

cheers

Did you lower the rear end too?

haven't lowered the back at this stage
left it raked

That makes front wheels to rub on the guards..