Foxbody engine shakes at idle only

Whats up guys i have 90 Foxbody mustang 5 speed, stock bottom end i did a gt40 heads/gt40 upper and lower intake and a tfs1 cam swap, 70mm TB, 76mm MAF with stock 19 injectors, bbk shorty headers, underdrive pulleys. The car starts fine and drives fine but just at idle the engine shakes pretty bad if rev it up the shake goes away. I already put new plugs and wires, new o2 sensors, fixed some vaccum leaks but still shakes, any thoughts? Thanks!
 
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Just did my harmonic balancer. Same problem went away . I got under it a little , and touched the side of the balancer with my finger while it was idling . Was off pretty bad.
 
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Check the fan clutch too. I had the bearings blow out of mine, and caused a pretty bad vibration. Easier fix than the balancer, so worth a look.
 
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Go back over your work. Sounds silly but simple things often are the problem.
Check timing, firing order, it could be a miss, pull the plug wires one by one while at an idle, you can feel/hear it drop a cylinder. Be careful, the wires will shock you if your not careful.
Compression test, I know you just installed the top end but strange things happen.
Harmonic balancer and fan clutch could be an issue too as mentioned above.
 
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Whats up guys finally had time to check over those things, i tried that touch test on the harmonic balancer and didnt really feel a wobble like maybe a bit but couldnt really tell, i also checked the fan clutch and mounts seem fine checked over my work everything looks fine, seems to be running a bit rich too i can smell fuel when its idling, here's a link to a video i took let me know what u guys think https://gofile.io/?c=EzbRzg