I think I might have 'found' and answer. I looked on the Registry site and found this for 1955 export Manhattans, which would be a 51363
1955 Kaiser Manhattan 4dr Export
1 51363-010370 150 5340 Tuzzolino ARG Provinci
2 51363-010839 Null CA form. Rice
3 51363-N10580 Borri ARG
4 51363-N10858 486 5343 Monti ARG
5 51363-N11014 Tilden GA
6 51363-N11015 480 5322 Lash OH form. John logan,
7 51363-N11021 481 5322 Hucker IN form John Logan, O
8 51363- 490 486 5343 ARG
5340 was the trim on one of our Argentinian member's car, and 480 has been reported on another car. Neither the colour nor the trim is reported on the North American 55 Kaisers, either the 51367 4dr or 51467 2dr. I am thinking that the interior would have been leather, and the number code is for the dye colour? That there were two 486 5343 indicates a pattern/colour matching, as all the others have different combinations. I recall that although there were ads showing two tones, all the Argentinian Kaisers were single tones, and the colour code might reflect this. Perhaps if he got in touch with Sr. Tuzzolina or the IKA club?