Front end shimmy

[Leatherback 57]

On my 1929 Leather back. My wish bone was broken at ball cap assy. Ball end was not worn but bought rubber style kit. Now I have shimmy at low speeds if there are any bumps in road. All components were replaced, all tight . Checked axle angle ok. Are there shims for caster and is it better to use stock mounting kit over rubber style?. Several club members have used stabilizer kit and said problem solved. Any input appreciated. Thanks