I just use the engine assembly stand. I built a radiator cart on wheels that rolls up to the front of the engine, and has a battery, switch-and-gauge panel, etc. A two-gallon fuel jug sits on the floor. The "legs" and the gauge panel swing away for storage; it takes up very little room when it's not needed. I use distilled water plus "water pump lube" during break-in; no antifreeze to clean up if things go badly.
This works great for carbureted engines with engine-driven fuel pumps. Have a garden hose available to mist the radiator if things get warm. I support the front of the engine with a chain to an engine hoist from the water-pump area. The engine does jiggle around a little as it runs, and I need to be careful opening/closing the throttle as there's some torque reaction when the engine changes speed. Most of the exhaust system came from a '67 Dodge Dart with the Leaning Tower of Power, adapted via flex-tube to fit whatever I'm working on at the moment. Quieting the exhaust noise is ESSENTIAL as you won't hear knocking rods or ticking lifters otherwise.
Pontiac 455 with rad cart:
You must be registered for see images attach
You must be registered for see images attach
You must be registered for see images attach
You must be registered for see images attach
You must be registered for see images attach
Making a run-stand, or adapting my "radiator cart" to an EFI--computer-controlled engine would be
significant work. You'd need an electric (probably in-line) fuel pump of at least the pressure required by your injection system; and a return system back to your tank. You'd need a computer plus wire harness for every engine-related sensor--and all the sensors. I suppose you could do without the O2 sensors; it'll run in open-loop. The computer would need to be grounded to the test stand just like it's grounded in the vehicle. And don't forget to include a MIL light and OBD-2 connector so you can view the data stream as it runs.
And, of course, the computer will have to be "tuned" to the engine.
Overall, I agree with Supercharged111.
Put it in the truck, use the truck wire harness and whatever computer you want to use. OR put a carb on the thing, a non-computer-controlled distributor, and a low-pressure inline electric fuel pump. Run the engine on the stand, then put install the EFI and computer systems before installation in the vehicle.