Exactly, you have the option of installing and going from there or putting oil in the crankcase and spinning it over or maybe forcing oil into the oil gallery by pumping it in.
I'm just saying, it's not a good idea to keep spinning the engine unless there's oil being pumped through the bearings. One way of knowing this is watching for oil coming up through pushrods to lubricate the rocker arms.
I usually start and run all engine replacements 20 minutes at high idle before installing in boats (such as stern drives) and I always make sure the oiling system is primed before cranking or starting them. It's probably not possible to fire up a 4-tec before dropping it in but maybe possible to prime the oiling system before cranking or during cranking it over with plugs out.
WHAT IF you drop it in and fire it up and the oil pump cavitates air thus doesn't develop oil pressure the first 90 seconds of running, the bearings will be ruined. Priming the oiling system avoids this possibility. Another alternative is by packing the oil pump with vaseline, many times new oil pumps come already packed with vaseline to avoid air cavitation during initial startup. Bottom line, the rotating assembly will be damaged if spun too much with no lubrication.
FWIW, while in storage sitting around, I find synthetic lubricants tend to run off and out of wetted bearing surfaces and cylinder walls faster than conventional lubricants. Synthetics are typically thinner, maybe that's the only reason why? Synthetics being thinner are more easily pumped up through the rotating assembly thus you might argue the oiling system pressure comes up faster.
I wouldn't argue against synthetic's lubricating properties but in my mind, dino oils provide better protection during storage.
Anyway, good luck and I agree with the above you really can't judge the engine until there's oil pressure throughout.
