That is a locking hood latch..... I've seen more of those here on OB that I would have expected........
It does have the switch for dual tanks, the markings for the switch are the black thing to the right of that hood latch, and the switch points straight down below the dash. It also has intermittent wipers. Another thing you may see if you buy it, it does still have the IVR (Instrument Voltage Regulator) and it if sticks all the gauges will read high..... like toward pegged high, just like the 80-86 trucks would do. These also have a "real" oil pressure gauge, as in it will move with oil pressure, it wasn't until the 92+ body they changed to the 7 psi moves to the middle of the gauge setup...
Also, looking at those dog dish hubcaps, this does NOT appear to be a full floater rear. The dog dish caps used on the rear were much deeper, not flush with the outside of the tire like these appear to be.... the FF hubs stick out farther than those hub caps do........
We've had a E-150 gasser in both body styles, an 85 and a 94. I personally put over 100,000 on the 85 while in College and it had 200,000 when it was traded in on the 94 that had almost 280,000 when it was traded on Dad's 12 F-150. Both had the 302, the 85 being the last year with a carb.
That also reminds me, not sure on the 75-91 frame, but on the 92+ check the frame rail area around where the steering box mounts...... that was the last straw on Dad's 94, the frame had started to crack and the box would move a bit...... he checked on getting it fixed, but was quoted nearly 4 grand for the repair, as the frame needs to be stripped of all the suspension, the broken section removed, and replaced with a good section from a doner, then everything reassembled...... This was not the van's only issue...... so it and his 97 7-lug F-250 turned into a 2012 Supercrew 4x4 F-150.....
If I had the money, I'd be headed to look at his van if you didn't get it..... I do like the E-Series Vans...... spent nearly 15 years, and almost 400,000 miles in them...... However, the E-Series vans were always Ford's "red-headed step child", and many of the improvements that were seen on the other Fords of the era were not introduced to the vans until a few years later........ I.E., they still kept the 8x6.5 lug spacing well into the 2000's when all the other Fords went metric in the late 90's.... Many of the changes that took place in the 87-91 Bricknose trucks, did not get moved over to the vans until the redesign in 92...... Ford didn't do a lot of changing on the vans, really the Econoline series vans really only had 4 body styles for the entire run from 61-15, the original "bus" design with the driver in front of the front wheels (61-67), the short nose with the wheel at the front of the van (68-74), the body that eventually received an IDI (75-91), and the one that ran through the release of the "Transit" (92-15). There were cosmetic changes over the years, grilles/headlights, location of badging...... but the basic van stayed the same through the entire run of a generation.