...and look at the frame where the isolated K frame bolts to it, especially around the rear bolt on the driver side.
bigredbird- thanks for the link to that Hemmings article, I've been looking for that issue!
I've been using this price guide.
Some obvious errors, but more detailed that KBB/NADA and less replacement cost biased than Edmonds/Haggerty-
http://collectorcarmarket.com/menus/pl73d.html
However, if you read the descriptions on Haggerty/Edmonds, you'll see that "the industry" rating of #2 is WAY above what most street guys would call a #2 car, and that most cars that aren't sold/bought professionally are #3 at best.
This chart does have yor 9K figure in between #3 and #4, but that's for a 400 car, and they don't even list a 318 as an option (one of those errors).
1973 PLYMOUTH ROAD RUNNER 400-225hp (8cyl-4V) AT
#5 #4 #3 #2 #1
2dr Hardtop 3675 8625 14950 20175 33450
Add:
440-280hp (8cyl-4V) 30%
4spd manual trans 5%
Power windows 3%
Sunroof-sliding 15%
Deduct:
340-235hp (8cyl-4V) -5%
3spd manual transmission -10%
No air conditioning -10%
Manual steering -5%
Bench seat -5%
Column shift -5%