Thats a cool truck--I have yet to own a '60-'66 GM truck,and always loved the styling of them,especially the '61 hoods with the eyebrows--and the Panel trucks of that vintage were the best looking ones next to the '56-'57 models..
My older brother had a '66 Suburban caryall with windows,had a 283 and a Powerglide in it...Turquoise blue with white on top,was a sweet truck..(had the tailgate though,not barn doors--booo!)..
I read a lot of that spec sheet,and its pretty interesting to note a '66 straight six 250 had 155 HP,and 235 ft/lbs of torque--that is nearly identical as a 6.2 diesel's specs,and the peak torque is reached at 1600 rpms,also much like the diesel...(I bet the 250 six would beat a 6.2 in a drag race!)..
The "Chevy" manual 4 speed is likely a SM420--those are as strong as a SM465,I have seen many in school busses and dump trucks of that vintage...it is surprising they had two versions of that New Process 4 speed with different 3rd gear ratios for the bigger trucks with 2 speed rear axles..
I have the rear half of a '62 C20 pickup frame that someone cut down to make a trailer out of it, sitting in my backyard--has the 1 ton rated coil springs and control arms (which were rotted and patched up with angle iron)--it has an Eaton full floating rear diff with 4:56 gears..not posi,as fas as I can tell...the frame is still solid as a rock,it was a shame whoever had that truck didn't just fix it up!..
I would love to find a truck of that vintage around here for a reasonable price--unfortunately the few that exist look worse than the "barn find" one,and people still want 3000+ bucks for one in sad shape...4x4 ones are even rarer here and priced higher..the '60-'66 trucks seem to rot worse than the '55-57's here,and the later generations,so its harder to find a good one..
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