Cranks but will not start?

The distributor is brand new. The original one broke, that's why I changed it, but in the process of putting the new distributor in I decided to go ahead and put an upper gasket kit on it. So, I don't need to take the distributor cap off. I used one of those bore scope cameras, or whatever they are called, and checked the cam lobes and crank journals as well as the inside of the cylinders. Everything looks fine. The engine turns over just fine. I checked the timing multiple times. I have checked everything over and over. Can't find anything wrong. At one point I removed the factory Delco theft lock radio and installed an aftermarket stereo. The aftermarket stereo worked just fine. But after replacing the distributor and gaskets and couldn't get it to start, I found out about the pass lock and anti-theft deterrent security system. From everything I've read I thought maybe I disrupted the security system. So, I put the original radio back in it. Radio comes on works just fine. Still no start. Cranks over just fine but will not start. When you first turn on the key all the dash indicator lights come on like they should. And when u turn the key to crank it all the lights go off like normal. Security light light's up to show its working but goes off within a few seconds like normal. So, I don't know if the pass lock is keeping it from starting or not. Or if it's anything to do with the security system. Idk what else to do. I don't know if it's in a limp mode or something or what is going on. The oil pump turns. I turned it with a long screwdriver when I installed the new distributor. So, it can't be locked up. The oil pressure gauge goes up while cranking it over, so I assume it's nothing to do with that. I'm thinking crank shaft position sensor. Is it possible the distributor cap could be faulty even though it's new? And there's a vacuum hose coming from drivers' side of the engine bay that has what looks like some sort of tee connector and from the tee the hose goes to whatever that is on top of the intake. But the hose was dry rotted and I haven't replaced it. Is it possible for that to keep it from starting? I can't find literature about the security system that makes any sense. And I keep reading all kinds of different things about how to set the timing when installing a new distributor. I followed the Chilton manual but it's also not my first time doing this. I know how to get #1 cylinder to TDC on the compression stroke. I also know there are two marks on the harmonic balancer. I know there's a mark for 6- and 8-cylinder engine under the distributor cap. But now I'm reading multiple different things about setting those timing marks. And now I'm reading that there's apparently another mark on the bottom of the block and the two on the balancer and the v notch and this other mark all have to be lined up when setting the distributor as well as #1 at TDC. So, do you have a clear legible picture of the timing marks? Do you have any literature about the entire security system and how to operate it? Do you have a complete vacuum line diagram that's easy to read? Every diagram I have found is not easy to see or figure out what is showing. I don't know what else to say or do. I have a Bosch OBD1 and OBD2 Scan Tool 1300 Series. I know how to use OBD Code readers. I'm not sure how to use the scan tool or if it works on my vehicle. Let me know what your thoughts are. Again, the vehicle is listed above. All transmission. The truck is all stock. No performance upgrades or anything like that. It acts like it wants to start when cranking the engine over. I have the original ignition key. But I don't have the key fob thing for it that has the lock/unlock and alarm buttons on it. If I don't get this truck to run. I'm probably going to set it on fire. Oh, the original muffler was rusted pretty good, so I cut it off. It still has the Catalytic Converter on it as well as the sensors.