often the idler arm will have 2-3 washers to space it in the K frame , make sure the washers are on top so the idler is a low as possible .
the other problem may be old soft engine mounts , the Poly Loc are a poly mount that interlock so they will not pull apart like the poor quality new ones made in India , this should lift the engine back to original height , Mancini has the poly loc mounts if you decide yours are in poor condition .