Toyota Repair: camry low oil pressure, low oil pressure, rod bearings

Question
The oil light is coming on at idle on my 1996 toyota camry with the 2.2L engine, 120,000 miles on the engine, checked with a master gauge the oil pressure was at 6-8 psi @ idle and 3000 rpm, I talked to a toyota dealer and they advised it was common for the oil pump to go bad, I put in a oil pump and although the oil light has not come on yet the pressure is still at 6-8 psi hot. am I now looking at bearings or is there anything I may be overlooking on these engines? If bearings, do you suggest just rod bearings as they take the most abuse or do both rods and mains (would cam brgs be ok) and is it practical to do inframe?
The engine acutally runs great, quiet, uses no oil.
Appreciate any help!!!!

Answer
6-8psi at idle is normal, at 3000 rpm it should be around 30-50 or higher, if the bearings were worn you should hear a lot of engine noise so I don't think that's the case,I suggest that you inspect the engine for possible sludge builtup, remove the valve cover for inspection.