If you’re considering a unique project, something that’s cheap and will reward: consider a Datsun 620 or a Datsun 720 pickup truck! Think about it: everyone knows about Toyota’s trucks and there are plenty of examples to be had. What if you want something that is rare while still having enough popularity to have most parts available for order. Both the Datsun 620 and Datsun 720 pickup trucks are rugged, cheap to work on, look unique and, in the case of the Datsun 720, could have been assembled in the United States.
Nissan’s Datsun trucks were known for their reliability, ease of use and ruggedness. The Nissan L engine was simple and reliable. Though not as popular as Toyota products, the Datsun 620 and 720 were, and still are, highly regarded.
“In North America, the 620 continued to use the Nissan L engine. The 1972 and 1973 models were powered by the L16 engine (96 hp), the 1974 model used the L18 engine (100 hp), and the 1975 through 1979 models used the L20B engine (110 hp). The standard transmissions were the F4W63 four-speed (1972 and 1973) and F4W71 four-speed (1974 to 1979). In 1977, the optional FS5W71B five-speed manual transmission became available. The 3N71 three-speed automatic became available as an option in mid-1972. This was the first series to offer an automatic transmission as an option (all model series before the 620 only had manual transmissions). 
Final drive gearing was 4.375:1. Side badges read “DATSUN 1600” or simply “DATSUN”. The grille badge was two colored stripes (one red and one blue) behind the word “DATSUN”. The 620 was known for its durability and weather resistance despite its small size, along with engines known for their reliability. As a result, the 620 was competing with the larger American pickup trucks, which in turn gave Datsun a strong reputation in the United States. A number of innovations were introduced with the 620: first long-bed (1975), emission control technology called (NAPS (Nissan Anti Pollution System)) in 1975, first extended-cab (1977), front disc brakes (1978), and electronic ignition (1978).” – – Wikipedia
Examples of the Datsun 620 run from a few hundred bucks for a junker to abouut $3,500 for a good runner. The Datsun 720 seems a bit cheaper with more examples available and modern amenities like extra cabs and three-speed automatic transmissions being available. Locally, here in Colorado, I have seen a few running 4X4 King-cab 720s going for $2,000 or less.
The best part about considering a modern classic like the 620 and 720 Datsun pickup truck is the amount of online support available out there. Nissan/Datsun folk are a devoted bunch who seem to genuinely enjoy the success of others when it comes to Datsun restorations. A buddy of mine, Greg Childs CEO/Owner of NICOclub.com mentioned to me that the Nissan community is very tight. Outlets like NICOclub.com can point you to the right direction when embarking on a project like this.
Who knows? By restoring a Datsun 620 or 720 pickup truck, you may find a solid little ride that replaces your idea of what a useful truck actually is. Trucks today are so big, expensive and over-complicated compared to these Datsun trucks. Imagine a pristine Datsun truck one in your garage and you may forget about these modern trucks.
Oh, and I have to say it. These Datsun trucks and damn good looking – especially the Datsun 620!
Speaking of modern Nissans, check out this Nissan Titan video!
More technical info from Wikipedia on the Datsun 620 pickup truck:
Datsun 620
Overview
Also called Yue Loong 753
Production 1972-1979
Model years 1973-1979
Assembly Kyūshū, Japan
Body and chassis
Class Compact truck
Body style
2-door pickup
2-door long bed pickup
2-door double-cab pickup (U620)
2-door extended cab pickup (King Cab)
4-door pickup
3-door delivery van
Layout Front engine, rear-wheel drive
Powertrain
Engine
1.5 L J15 I4
1.6 L L16 I4 (1972-1973)
1.8 L L18 I4 (1974)
2.0 L L20B I4 (1975-1979)
2.2 L SD22 diesel I4
Transmission
3-speed 3N71 automatic
4-speed F4W63 manual (1972-1973)
4-speed F4W71 manual (1974-1979)
5-speed FS5W71B manual (option from 1977)
Dimensions
Wheelbase
2,545 mm (100.2 in)[4]
2,785 mm (109.6 in) (G/GN620)[4]
Chronology
Predecessor Datsun 521
Successor Datsun 720
