Weird noise after 4 speed install

What cam are you running? 268/276/110 Voodoo703
Are you running Solid lifters? nope.
What's the idle speed?
the Idle-timing? 18*
the Setting of the Idle-mixture screws?
Have you set the T-slot sync?
OOps some of that is in Post 47

IMO
because she sounds to be idling pretty fast, with a lot of timing, most likely the T-slot to mixture screw relationship is out of whack and the engine is just struggling with AFR. Make sure your secondaries are closed up tight but not sticking.
Furthermore, at 18* timing, your engine is making too much idle-power, and the power-pulses are hammering the driveline.

I had your exact combo a few years ago, except with a Hughes cam, and 11.3Scr. I idled it at 14* in the distributor and 650/700 rpm in Neutral, with no bypass air. My T-slot exposure was square.
To reduce the power for parading, I reset the idle-timing to 5*.
That cam would idle at 500/550 in low gear@ 5* advance, pulling itself all around the parking lot, with no help from my big right foot, nor the left one. With 3.55s, that was 4.25 mph with the standard 2.66 low, and with the 3.09, it was 3.6mph
I ran the cooling system at 207*F

But I just gotta say, man that sounds like a lotta valve-train noise.Mine was quiet as can be.

I'm running Fitech Fuel injection so it's a bit different than a carb.

My idle speed is 800, I can adjust this down along with my idle timing with a touch of a button.

My AFR at idle is 13.4 ish, can also be set.

I didn't think the valve train was loud, but I guess I have nothing to compare it to. I'll pull the plugs tonight and remove the valve covers and inspect.