If it's a roller, prime the heck out of it that morning, get all your stuff set up and light it off when you are ready. I would leave the thermostat out, or drill a .0625 hole in it, just so you don't have to burp it. However it should be easy. Take your time, no emergency with a roller.
It's not going to eat a cam, so as long as all the parts have oil, you'll be good. I like any name brand 10w30 performance oil if hyd roller. If solid roller, likely even less fussy on oil weight. Eventually the EFI will want a thermostat, but for first fire up, clean water and no thermostat can make leaks less of a big deal. Then when you have it running and idling, you can cool it down and put coolant and a thermostat in
Now, I do not particularly like a 5 quart pan, but if that's needed for the application, be sure to mark the dipstick before you prime, and then get it back to the full mark after. 6 quarts in a performance FE isn't much
As far as break in, if a racer, likely a mellow run to see what's going to be funky, then have at it. If a streeter, I will do a couple circles around the block to be sure I won't be walking, and then get a good run with some accel/decel load, watch the gauges, but in the end, just run it. No fancy timing settings, just set it up and let it get a little time on it