[Xeen]

The CPP sheetmetal engine stands will allow the tranmission to clear the low hump trans tunnel with a 4L60E even when moved to the I6 frame position so no worries there.
I am using the truck pan in mine but if you ever lower the truck more than 4.5"/6" you will need to get a low profile pan.
One more thing, the 1" forward LS adapter plates aren't going to work, you need the "stock location" LS adapter plates because the 1" forward LS adapter plates will throw everything out of wack, the engine will be too far forward and cause the fan assembly to have clearance issues with the core support and you will have to lengthen your driveshaft which costs more money, keep it simple no need to reinvent the wheel here.
You will be able to sell the 1" forward adapter plates with no problem so don't worry about that part.