1992 F250 460 runs poor 900-1300 rpm

Barn find here. 1992 F250 with a 7.5L 460 ci engine. Only 40,700 miles. Was not running and a busted column due to lost keys. Replaced column and got it running. Ran terrible! New gas, fuel filter, fuel pump, plugs, wires, cap/rotor, and O2 sensor later it runs very well in most rpm ranges. Engine shakes badly from 900-1300 rpm sitting still, and shakes harder when driving it. If you nail the gas it winds right up with no issues driving or sitting. Fuel pressure good (43 psi). Applied vaccum to EGR and it fell on itself (EGR good). swapped TPS's with no change (TPS good), swapped MAP's with no change (MAP sensor good). Anyone have any ideas so I can stop throwing parts at it? Any help appreciated! :banghead: