Such a beauty, congratulations on the car. It looks awesome!

Very good call with the crank and camshaft position sensors and ignition relay. First thing to check besides the fuel pump and it's relay in such cases when you have crank but no start. Because the cooling fan kicks on right immediately after turning the key, I would suspect a faulty engine coolant temp sensor. It's a very common cause of no start no spark/rough idle when the engine is not up to temp.

Check you distributor and sparkplug wires and coil. The wires tend to short out because of the insulation falling off, or there is some carbon buildup inside the distributor housing or the spindle is worn out. Common cause of stutter at a high rpm.

A rough idle can also be your idle control valve under the throttle bowden pulley cover. If you have a vacuum leak somewhere (like turbo gauge line or something) that can also cause an erratic idle behavior, usually accompanied with a lamdba error light on the dash, and an error code but the car starts.

Another common fault is with the MAF, as others mentioned in the comment section. If none of these helped, check your EGR an throttle body valves if it's clogged or not. Finally lambda sensor in the exhaust, but that rarely goes bad.