fuel trim question

[1iwilly]

hello to all
when monitoring the fuel trims what are the good reading to look for.??still chasing a lean condition after a few more adjustments now at idle i see more + than - i was seen before LT-1 is down from 3.8 to 1.5 LT-2 is down from 3.8 to 2.5 as of today ST-1 is more in the 3.1 to 0.7 at idle compare to before -1.5 to -.07 ST-2 3.5 to -1.5 this is after changing 2 pre-cat 02 and bank-1 sensor 2 giving code po141 heater malfunction.next trip out i'll take pic of at ildle from start up then after warm and while cruising.thanks