So i finished up a 4.6 flanged liner bosch swap into my disco few weeks ago. just got the first 1k onto it. Most everything seems fine but had few lingering questions was hopeing somebody could help answer. im still runnin my stock 4.0 ecu. I have read multiple times over about internally switching you ecu from 4.0 to 4.6 but on at least one occasion i read a post saying that it only actually changes essentially the labeling not actual perameters, whats that truth. i dont want to pay a garage to switch it if it doesnt do anything in actuallity. It would make sense to me that it would be a labeling change not a parameter change. i know both ecu's have same part number but i have a hard time believeing that every ecu has tuning for both engines. Secondly my 4.6 long block came from a shipping auction. its got a 4.6 crank and after removing the head flanged liners, and its never been fired thats all i really know about it. I found one striking huge difference while bolting on my 4.0 gems parts (other than the crank senson and cam sensor bs). My block didnt have provisions milled for the oil pickup tube that was on my 4.0 and resulted in alot of costly bs. i had to swap to a d2 oil pan, pickup tube and oil pump/front cover. Other than the cost of the d2 parts i didnt have my only issue running about 9/16" spacers behind my water pump pulley to make it line up properly. so my question on this is why no oil pickup milled in my block? i assume since the front cover design changed to not utilize the pickup tube to the block they quit milling them? And does this mean d2 accessories pulleys sit 9/16" closer to the block. Sorry for my long rant and to all the people who have no clue what im talking about, but any thoughts on the ecu and water pump spacing would be apreciated.