Still think 20k is tight assuming all it has is junk growler airbox + hurricane catback & blown 6.0.
Add these up
vcm otr
hurricane or pacies extractors & metal 100-200 cell cats
d.o.d delete kit
cam/lifters
trunion uprgrade
mafless tune
That doesn't add 2nd hand 6.0 or ls3,stall conver or labour + little things