The final task of a long time in coming solution for this 83 B23F rough idle was to set the valves at least to 0.018"..two are at 0.019" clearance at TDC.
The rough idle plagued me prior to re-building the engine at 445,000 miles.
1.compression:150,130,160,180,(psi)cold w/ 4 piston pumps; no/oil on the rings.
2.leakdown:28,50,20,15,(psi)lost past rings or valves or both.
3.re-sleeved block, re-used pistons, new rings(Sweden)$1,099.00 machine shop.
4.Con-rod and crank bearings new std,(no crank machining),passed plasti-gage.
5.Head= new seals, hand lapped valves.
Still ran rough. Fuel pressure 25 psi= new tank pump psi= 27psi,new main 30 psi.
New AMM and O2 sensors...still ran rough.
Could be the valves. Indeed it helped make the smoothest it has been since I can remember. Did not go to 0.020" as it has been suggested around some boards, but at 0.018" it did the trick here.

Thankyou so much for posting solutions...this is my attempt to help someone in return.
T