"I would like to pass along a couple of tips for better operations.  Many thanks to Curt Fortenberry for passenger car decals and to Roundhouse Hobbies for the diesel decals.  Based on my research, the typical consist is as follows:

If you intend to model the full train, this is a long train with fifteen 85' cars.  It should probably be run only on the largest of layouts with large radii!

1) McKinley Explorer cars (also available in N scale). 

I have 5 cars.  The typical consist is 5 or 6.  These are very colorful and get rave reviews at the club however, a few improvements for operations/appearance:

a) The three large round tabs on the side of the shell are a little unsightly.  I used a fine pointed silver paint pen used to make them match the sides better.  I have not done this yet, but the best solution is to fill the holes with a rod of styrene.  This can be easily carved/filed to match the corrugated sides and a touch of silver paint should leave it  almost invisible. Feel free to repaint the whole side if you like - but it's probably not worth it.  Leave about 1/32" of the styrene rod protruding on the inside.  VERY lightly taper the tip of the protruding portion on the inside with fine sandpaper or a nail file to make it easier to insert into the frame later.  Cut off the tabs on the car frame and drill a hole the same size into the frame - err on the small side and make it larger later.  The key is a snug - not tight - fit.  Reattach the shell by inserting one end first and then the other end by bending the car frame in the middle.  Finally, spread the sides and insert your styrene tabs into the holes that you made in the frame of the car.

b) Detach the truck and coupler linking (very easy - the link just breaks off with a light twist).  I am a junk "pack rat" so I save the washers and links for piling scrap around the engine yard after weathering with rust colored paint and or Dullcote.  I "froze" the couplers with ACC.  These car bottoms are not made of styrene - I believe it may be Delrin - styrene glue does not work. You will have to drill out the plastic center pin on the coupler box and insert a #2 screw to really hold the coupler box.  Make sure your drill bit is just slightly narrower than the screw.  From the voice of experience - the plastic is brittle and will break if you don't use a bit that is large enough.

c) Replace the plastic wheelsets with metal wheels.  I used 36" Proto 2000 wheelsets.  You can improve these even further by using the Reboxx Exxact socket which is a precision tool to carve your truck sockets to the exact 60 degree NMRA standard (see their website at www.reboxx.com).  This is much cheaper than buying Kadee or Kato trucks and I would say the performance is almost as good in most cases after using the Exxact Socket (I am NOT on commission to Reboxx!)

2) Alaska RR cars (the base cars are also available in N scale). 

I did some further research and you are correct.  The closest approximations to the ARR are Rivarossi cars.  I would recommend buying one set of baggage, diner, dome and coach plus two coaches for a typical consists.  The diner, dome and baggage are very good approximations to the UP origin cars such as numbers 400, 500 and 100 respectively.  The window arrangement on the coaches are quite different due to the rebuilds.  The Rivarossi coach has about 11 windows, the real coaches on the ARR have about 16 windows.  The rivet (and window) counters can see a very good article in the March and April issues of Model Railroader about how to reconfigure windows to the prototype.  I'll reconfigure the windows in about 30 years after I retire.  For improved operations:

a) Body mount your couplers unless you have very sharp radii (under 24").  If you have sharp radius curves - as they say in Japan, rots a ruck! 

b) Replace your wheelsets with 33" wheelsets (anything larger will rub against the brake pads)- use the Reboxx Exxact socket. You may have to bend back the brake pads back even with the 33" wheels - keep some liquid styrene glue handy - you are guaranteed to break a few of the brake pads or at least severely fatigue the plastic.  Just a touch of glue after bending should strengthen the joint again.

Right now, you will need to purchase the Three Brothers SP 6 window bi-levels for your base model shell (recently launched in N scale - I think there is an announcement in the March or April MR).  According to the website on 4/2/02, the Three Bros. HO versions are still in stock at Walthers (item #713-602).  However, it APPEARS that Walthers may have purchased the molds for these and will be making them eventually.  This is based on the recent launch of the CNW 4 window bi-levels which appear to be remakes of the Three Brothers Versions. 

I am going to wait. I have my hands full painting ARR cars and renumbering  Atlas GP-38s for now.  Making the Princess cars is a project in itself and involves cutting off most of the top of the car and building the smoked glass domes from scratch.  It may involve changing a double door to a single and I will need to find a source for decals.

Pictures coming soon!