I did it once - a 350 just hanging from an engine hoist. Biggest issue was the noise - it didn't even have exhaust manifolds never mind mufflers. It caused quite a bit of excitement in the neighborhood.
It was a while ago, but I remember how I handled the cooling system. No need for a radiator. I just had a lower radiator hose connected to the water pump as normal. On the other end, I inserted an 1 1/4" X 1/2" bushing and clamped the hose around it. Screwed a 1/2" NPT male X 5/8" female garden hose adapter into the bushing. Attached a garden hose to the adapter and opened the sillcock. Result was an endless supply of city water for cooling. I pulled the t-stat IIRC.
Also, I didn't want the cooling water that was exiting the thermostat housing to just flow all over the front of the engine. To get the outflow away from the engine, I just attached a piece of an upper radiator hose to the t-stat housing as normal. Then I shoved a pool vacuum hose into the open end. The other end was led away and into the woods or something.
Gas supply was just a long piece of rubber gas line with one end attached to the fuel pump (pump was an engine mounted/mechanical) as normal. The other end was just submerged in a 5 gallon gas can. I made sure the hose was long enough to keep the gas can well away from the test engine. I had no idea what might go wrong - but a fire would have certainly made things worse.
A small hot wire was clamped to the positive terminal of a battery.The other end was connected to the BATT terminal on the distributor. Oil pressure was monitored with a gauge screwed into the oil port behind the distributor. Coolant temp was not monitored, it was assumed to be okay because of the flow of city water.
A cable was connected to the B terminal on the solenoid.
Cranking was done by attaching jumper cables to the good battery. Then on the engine side, first the positive clamp was attached to the cable going to the solenoid. And then, when everyone was ready, the negative cable was touched to the block.
Be advised; when the starter motor starts cranking the engine, the block will twist around on it's own axis due to internally generated torque. Not too much, but enough to get your attention. If you have never done this before, seeing the motor twisting on the chain can kind of make you a little jumpy.
But after it starts, the torque mellows out and you just have to get used to the noise - and let me tell you, it is LOUD. But you get over the noise pretty quick and after that the project becomes basically a tourist attraction. Everyone in the neighborhood will want to see what in the hell is going on. If I was going to do this again I would probably let folks know in advance.