My .02 again, Friday night kicked back and a few suds, long. Sider your assumption is probably good, go were the bucks are. How much money did those high dollar 67-72s have in them? If they paid to have the work done you will get one amount. If they did the work themselves you will get another amount, and it probably won't include their time. Why didn't they include their time because they enjoyed doing it.
Another consideration is maintenance. Old cars and trucks are high maintenance, ball joints, A arm bushings, cams, and on and on. One advantage of the 67-72s are they are still listed in most autoparts stores databases. If you crash a fender though your are competing with everyone else who thinks the 67-72 truck is the truck to have.
Here's an example. The last truck I bought was my 68, with 113K miles on it, 327 V8. The owner was asking $500. I thought that wasn't a bad price despite the 3 tone primer patches. For the most part it was pretty straight. Ther were some dings and dents under the primer patches. It's missing most of the chrome across the hood and down the fenders. There were some carburator problems. Even still for the for the price I thought it was a good deal might even make a little money on it. Almost any truck in the Silicon Valley, CA will sell for $2000. Seon might sympathise with me on this. Problem the truck had not been registered for five years. Went down to the DMV and ran a check on the VIN number, answer not in the database. Cool no back fees to pay. Bought the truck, PITA to get home, carburation is a problem. Disassembled the carburator, it was obivious fresh rebuild from some parts store. It also looked like the new kid on the assembly line did the rebuild, bent up air tubes on the Quadrajet. Bought another carb off Ebay $45, put a kit in it. Dropped in an HEI, I'd got in a deal on another truck. Truck now runs and starts every time. Time to register it, went down to the DMV. Stood inline for an hour, got to the window and gave them the pink slip signed over to me. The clerk runs the VIN number and says "Do you want to pay the late fees?". I'm thinking there are none and say "OK". The clerk says "That will be $852". OUCH!!!! Seems when I checked on the truck a month earlier that activated the record, DAMN. OK, I'm still not into it too bad. The trucks still not performing quite right, pops thru the carb when you put your foot to it. Most noticeable when tuning it and you slam the throttle open. I'll adjust the valves. I pull the valve covers off and I go to #1 to adjust. That doesn't look right, it's not moving up and down like it should. I look at the other valves and a third are not moving like they should. #*$&@), Cams gone, ordered a cam. Got the cam and a day later, new cam and lifters, runs great. End of long story, I might reasonably break even if I was to sell it now. So I'll drive it for a while. It's a nice truck now, runs good, rides better than my 63. There's a problem with the clutch I haven't quite figured out yet. When it's cold, the bucks like an #%$$, unless I run the RPMs up to about 3 grand. That's one of the reasons I still prefer to drive 63 with the big 292 six. That big six has so much bottom end torque, I can pull tree stumps at idle.
I guess what I'm trying to say Sider is buy what YOU want. You don't know what your getting into with an old truck or car. Consider what it's going to cost you to keep it running. If you buy what you want then when you have to put money into it, you may not feel as bad. How much work are you going to do it and how much are you going to pay to have done. IF your going to put money in it, you'd better find out how much was in those high dollar trucks. The only truck or car that I know that will sell for top dollar anytime, any where is the original low mileage, all options. The alternative is the low mileage Grandparents car. It's usually cheap and well maintained.
Larry
68 C20 327 daily driver
63 C20 292 Camper truck
65 C10 ? Custom Cab AC,PB,PS,$flasher