I'm about to pull the trigger on this older build and was wondering if anyone could give a heads up on what to look for. I assume it will need batteries soon and am ok with that. Anything else I should be checking on?
You should look for acid drippings and mist damage to parts of the unibody and components below and down wind of the batteries. The battery trays and tie down frames may not fit the new batteries you might use. I'm guessing there are 16-25 batteries, with most of them taking up a lot of the bed. Also, I'm guessing the gross weight is pushing the max limit. The good news, battery weight wise for~the same amount of range, if you replace the LA with LiFePO4 batteries, it will save ~1/3 on the weight. Batteries with other chemistries might save you up to 2/3 the weight.
The controller probably is a Curtis 1231. These controllers were not known for their performance abilities. Slow acceleration and low top speed are the results.
Practically speaking, could this vehicle be driven in the rain, snow, and dirty conditions with the exposed electronics and electrical connections? In an accident, first responders really need to have orange color coded HV wiring and well marked wire disconnect cut sections. Insurance might be a problem.
It looks like you are in Colorado. You should check if there are tax credits for purchase of a used EV, or for a conversion. It may not apply to non-OEM vehicles.
If you are just into having an EV, something like a used Leaf might be a cheaper alternative with much better performance, potentially quicker charging, and quicker to get on the road. Some people are just into messing around with EVs. If this is your case, go for it!