I'd have to look back about two computers to find my install of the DEWLine scenery but...
I am finding that the reference for the runways are about 40 degrees out
it's a matter of geography. At the latitudes of most of those airports a magnetic compass is unuseable (in fact there is part of the airspace designated as the "Area of Compass Unreliability")
Conventional magnetic compasses sense magnetic direction by detecting the horizontal component of the earth's magnetic field. Since this horizontal component vanishes near the magnetic poles, magnetic compasses are highly unreliable and unusable in an area approximately 1,000 NM from each magnetic pole. Within these areas, air navigation tasks are further complicated by very rapid changes in magnetic variation over small distances. For example, when flying between the magnetic North Pole and the true North Pole, a heading of true North results in a magnetic heading of South (a magnetic variation of 180 degrees).
http://code7700.com/high_latitude.html#navigation (Go down the page to Navigation Issues)
Here are a few references on the subject:
http://www.albertaclassic.com/nav.php
http://geomag.nrcan.gc.ca/mag_fld/compass-eng.php The map will show you how extensive this is.
http://aviation.stackexchange.com/questions/351/vor-orientation-near-magnetic-pole (Some discussion by pilots on the subject)
The Al Gay/Bear Baker scenery was for FS2002 and updated with dew_stns.zip by Curt Jardey (avbl at FlightSim). In the past couple of years Roger Wensley has put out a whole bunch of new sceneries (about 30) for many of the DEW sites. They are more modern and may lack some of the old station buildings, etc. but are crafted using SceneGenX and more accurate (probably don't have some of the frame-rate issues the old scenery was known to generate for some people). A Search for "DEW line" (the space is needed) on FlightSim will find these, as will a search for "Roger Wensley" (but that will also get you dozens of other scenery files he's done - although many are worth looking at...)
The general technique has to be a newly-learned process.
Since navigation in FS (as in the real world) is generally based on Magnetic headings things get difficult 'up there' where everything is done in Degrees TRUE. In the pre-war and DEWLine days it led to numerous accidents, esp. for novice northern pilots. Long-range polar flights normally had a) a navigator and b) some alternate form of navigation (celestial, DECCA, LORAN) that showed position in Lat.Long (In FS we have Shift-Z) and crews navigated by flying from one Lat/Long coordinate to the next. That equipment and skill-set will get you to the general area but is too cumbersome for approaches in many cases.
I doubt the problem of Magnetic Declination is modeled in FS but the Variation issues certainly are.
First thing - don't plan on flying a mag. heading to an airport or an NDB then a new mag. heading to line up on final. The now-common practices of direct-to and straight-in approaches didn't happen back then. One homed to a beacon (ignoring the mag. compass) then flew some home-made orientation procedure. Without a global nav installation (there are a couple for FS that do work but can be problematic), if using the ADF, fly to the beacon, then either a visual approach to the runway or an orientation approach - often a 'teardrop' pattern - using the beacon (only) to turn back toward the airport and hopefully align near the runway.
Bad weather? Historically many flights were cancelled or delayed due to low vis conditions or ended up piled into rocky outcrops when pilots tried to press onward... the accident stats are impressive/depressing.
Oh, the GPS is of questionable help as it also references Magnetic North so following the pink line is no easy answer. To make it worse, the FS9 world is not a globe, but a cylinder which is why you can get some crazy headings and angles trying to fly near the poles ("over" is impossible in FS9).
IF you are serious about wanting to fly the area using realistic nav. equipment and procedures then you will learn a whole set of new skills. Aviation charts will show which airports are laid out using *True. Problem is, many of the FS airports were not corrected for this, or not identified as using True headings for runway alignment. The old scenery is therefore potentially dubious, but still fun.
Equipment:
Nav. was done by the old methods: Celestial, map reading, time/distance and most of this can be replicated in FS9. There is a celestial nav 'gauge' available, and a "drift Meter" which can help staying on a straight course.
VORs, of course, weren't available in the high north for most of the DEWline era but standard equipment was
TWO ADF radios (one tuned to the NDB at point of departure, the other to the destination NDB). There are a couple of dual ADF radios floating around (I use Mike Wagner's but can't find it uploaded anywhere, but the default DC-3 radios and RMI work just fine. The second ADF needs to be enabled in the aircraft.cfg file (no, you can't just add a second copy of an ADF1).
Oh.. make sure you have enough fuel to go to an alternate or back to pt. of departure
Practice... and watch for a DEWline-themed competitive event possibly later in the year.
Rob