From a wikipedia TLH entry, it appears that there's about 200 miles between HV-GB and Cartwright Junction that is still packed gravel (wonder if it's actually tar and chip?), left to be paved.
From all accounts of recent travellers, it's Route 389 from Baie Comeau, QC to Labrador City, NL that really needs some help.
A couple of youngsters from Ontario, Canada known on youtube as "A Guy, a Girl, and a Campervan" have videotaped a lot of the TLH route a few years ago when they did it. If you're interested in how good/bad/ugly it is in spots.
