I just reassembled my KA-swapped 210 with a rebuilt longblock I bought from a local enthusiast since my old block threw a rod, but it barely runs and makes some noise (see video). https://youtu.be/G_7iA7M7KBs

He had installed forged rods, clevite bearings, cometic head gasket, and ARP studs. I took it and replaced the timing chain assembly before sealing up the timing cover, oil pan, and valve cover. I used the rest of my known-good parts like intake manifold, distributor, etc, with refreshed hoses, new gaskets, new plugs and wires. I'm very methodical and cleaned and lubed every bit of the assembly that I did, followed torque specs in FSM, and was extra careful of the timing especially, following the FSM and the Jim Wolf guide that is often referenced.

In spite of that, the car wouldn't start when I first attempted, like it wasn't even trying to fire. I removed the distributor cap and found it had rotated a tooth while installing it and the timing was retarded. At TDC on the compression stroke of cylinder #1 I again installed the distributor and verified the rotor position with the manual (one tooth advanced vs where it was previously). This time the car fired up but it was very rough and shaky as shown. I've avoided letting it idle like that longer than 10-15 seconds at a time cause it sounds so bad.

Could it be that the timing is still off a tooth, and advancing the distributor would help? I'm hesitant to try since it appears correct and I want to avoid knocking/detonation. Is it a probable cause and/or safe to try one tooth past "correct".

I noticed traces of fuel in the cylinders so I left the spark plugs removed today to dry out, and I'm planning to compression test it this evening so I can report back with that. Can someone experienced with the KA give me their thoughts on how bad this sounds and what it may be? I know it's difficult by video but I'd greatly appreciate it. The guy who sold me the engine is rather helpful and is coming over to take a look with me, I'd just like to get some input here on DO's and DON'T's so I don't mess things up futher.

https://youtu.be/G_7iA7M7KBs

Thanks,
Steve