I'm actually planning a r-t drive from Chiang Rai to Nong Kai (no, can't take the boat down the Mekong).

I can't find any good maps, but the best I've found is large scale and shows no paved roads in the area northeast of Phitsanolok (between Phits and Laos). I'm planning on delivering a load of farming material, so it's not so much a sightseeing trip as it is a practical trip.

Any tips are appreciated.

From Phitsanulok go East over the mountains to Petchabun Province. When you come out of the mountains you'll be in Amphur Lomsak. From there go North to get to Loei.

If it was me, I wouldn't go into/through Lomsak, but rather continue on the road East from Phits and go over another set of mountains towards khon Kaen.

Either way will get you to nong Khai.

try Lanna Souvenir - by Karagaron - for a good map. maybe B100.

yes, there is a road. an OK one, I think. but better to go to Pitsanulok, maybe...

the mountains can be big, the roads windy, and its raining today...

Pitsanulok then east - not bad roads to Loei City.

I was considering doing it myself, for visa run... thinking Loei maybe a half-way place to spend the night...

I would not bother to drive to Loei if your destination is Nongkhai. I would use the highway system of 11 to Pitts then 12 to Khon Khen and then 2 to Nongkhai. Back roads with a load are likely to be slow and costly for fuel. If just to Loei there is a turnoff about 25km south of Uttaradit (guess from looking at map) on route 11 to road 1246 and then turn off that after 10-20km to 1143 to Nakhon Thai to 2013/203 to Loei.

As Lopburi says, about 20km south of Uttaradit turn East onto hwy 1244 then right onto 1246 through to Nakhon Thai then left onto 2013 to Dan Sai where its 203 into Loei. From Loei its east on 210 to Udon Thani or the scenic route north on 201 Chiang Khan then follow the Mekong east to Nong Khai on 2186.

The roads are all paved and usually in better condition than Hwy 12,I did this trip every month for 3 years and regularly cut 1.5 hrs off going the long way round ,very scenic trip..