Crank no start issue?

Okay, if you have spark have you checked that it's in time? Next try spraying some fuel into the intake and see if it will at least try to start, that will help to narrow down if it's fuel or spark. If it has been setting a while it could be the injectors have gotten clogged with dried fuel, spraying fuel in may help to determine that. You can also try to power the pump directly and bypass the relay and see if it helps to have constant fuel. Another thing that would show would be if you smell fuel in the exhaust. Then for spark a spark tester plugged into plug 4 as a quick test, if the spark is there but weak, connect the tester in line with the coil and test there. If you have good spark there, then you will want to pull the opti off and clean under the cap as it could be corroded from setting.

This is a pretty good video on testing it in the car:

https://www.youtube.com/watch?v=9szDBiEX3cg

The signals he talks about will be there during cranking as well. You could use an old school analog meter to watch for the square wave or if you wanted a cheap scope would really be a better thing.

That spark should be fine. As it seemed to start on spray I would go after the fuel system. You have 45 PSU at the test port so either the injectors are not firing, or they are clogged. I would go to the fuse box with a test light and verify that you have power to both injector 1 and 2 fuses, then go to an injector on each bank and unplug one and see if you have power on the black wire. If you do then take a mechanics stethoscope and use it to listen to the injector, you should be able to hear a defined click as it triggers. If it sounds muffled or nothing at all the injectors need to be cleaned at least. That can be done by removing them and soaking the tips in a carb cleaner. Then test again. Or if you don't want to fight with them, just get a set of matched injectors and install them.
I would also worry about how old the fuel in the tank is, especially if it had ethanol in it. For that you could use a jumper wire to battery positive in the fuel pump fuse to power the pump, disconnect the fuel line at the fuel rail and use the in tank pump to remove the old fuel, dump in 4-5 gallons of new fuel and pump a half gallon of that through, then reconnect it to the rail and put the fuse back in and see if it starts now.

If the lack of power was at the connector I would check the harness, corrosion in a connection could stop power out to the injectors.

Okay, if you tried them out of the car and they failed I would replace them. I would also check the power feed to each one just to be sure that it was the injectors failing and not that there is a problem now from that failure. I have seen shorted injectors cause a driver circuit failure due to the higher current from the shorted parts.

Great to hear, Now get it out there on the road! 'Vettes deserve to be driven.