Depends on the engine and where the shims are located.A valve check on the Forza should be really quick and easy I would think. After which, if adjustment is needed you can easily work out the size of the shims needed and pick them up from your dealer.
Some engines the shims are above the bucket and can be removed with a special tool.
Most engines these days have the shims under the buckets and the Camshafts need removing to get at them

Andy