As promised, here are the results of Bicycling magazine's 1984 Guide to Loaded Touring Bicycles:

LINEUP:
According to both the 1984 Guide and the 1985 Raleigh catalog, the Wyoming is the entry-level bike in Raleigh's touring lineup, followed by the Alyeska, the Kodiak, and the Portage.

TUBING:
According to the 1984 guide, the Wyoming, Alyeska, and Kodiak are all double-butted CrMo in the three main tubes, whereas the Portage is double-butted (or taper gauge) in all tubes.

This is somewhat at odds with the 1985 specs, which indicate that the Alyeska, Kodiak, and Portage all use Raleigh 555 tubing (although there is no indication in the 1985 specs as to which models are 555 main tubes only.).

Also, the 1985 specs don't indicate what the Wyoming tubes are made of. This could mean they're hi-tensile steel, which would conflict with the 1984 Guide, or it could be an oversight in the Raleigh specs, which would seem unlikely.


GEOMETRY:
According to the 1984 Guide, the geometry of the Wyoming, Alyeska, and Kodiak are identical, while the geometry of the Portage differs slightly.


COMPONENTS and TRIM:
According to the 1984 Guide, the main differences between the Wyoming, Alyeska, Kodiak and the Portage are:

1) Different component groups for each higher level of bike in the Raleigh line-up;
2) Double crankset for the Wyoming, triple cranksets for the Alyeska, Kodiak, and Portage;
3) 1 water bottle braze-on for the Wyoming, 2 for the Alyeska and Kodiak, 3 for the Portage;
4) 40 spoke rear wheel for the Alyeska, Kodiak, and Portage;
5) Higher levels of trim (whether racks are included, etc.) at each higher level in the line-up;
6) 650B wheelset on the Portage.