Front Lower Suspension Bracket packing

[andysredmini]

Our front lower suspension brackets need packing out by about 1.5mm. would it be better to just make some new brackets 1.5mm deeper?
If packing is the best option then how is best to do it? Do you cut some 1.5mm steel to the 25mm width of the box section and the 40mm width of the bracket, weld it on then weld the brackets to this?

Many thanks in advance

Andy