Rough Idle, esp when cold, stall in reverse
 

I have a 2000 F350 7.3L that tends to be a bit hard starting (you got to crank it longer than it should), and then when it does start it will idle but almost as if it is missing, it will drive in forward gears (its an automatic) but if it is at all cold it WILL stall when put in reverse. Symptoms generally go away when it warms up...except it still seems to have a slightly rough idle and slight roughness when driving at any speed. In the past, I have had the diagnostic scanner hooked up and it will come up with a bad injector...I get it replaced $$$ and then about a month or so later the problem seems to start all over again...I have replaced 3 injectors this way $$$. Any thought on this before I do the 4th - 8th injectors. This truck has exactly 100,000 miles on it. It was perfect until the High Pressure Oil pump went bad (what an oily mess, however it still seemed to run great even while spewing oil - kept adding oil until I got to the shop - it never got low on oil) and it has never been quite right ever since. Any and all good thoughts would be MUCH appreciated!:) HELP