The best aspect of this diy mod is deleting the huge, obstructing stock airbox. With the old airbox removed (but useful parts salvaged & reused) ,access to 4,5,6 from above is hugely improved.
One small detail The MAF tube is 3" at the intake end and 3-1/4" where it connects to the corrugated hose. So think carefully about that oddball 3-1/4" size(82mm+/-) before you just buy a 3" Spectre 9405 MAF tube.
I did buy the 9405 but made a rubber sleeve/adapter for one end.
The other idea is to use the cavity between the inner and outer fender as a cool-air plenum and air filter box. There are lots of creative ways of using UNI air filter foam in that space. And it should be a cooler location than the stock airbox which sits right above the Bank 2 header.
I found it very useful to remove the hinged ,metal body panel .Not just the engine cover,not just service mode, remove the entire rear cover that abuts the truck lid. It is the huge arc shaped 'lid' that fits forward of the trunk lid.It is just some pins and E clips.That makes it sooomuch easier.
This link may help:
intake install step by step with pics and video
The obvious problem in the diy is the hot,dirty location of the new air filter and the lack of detail on how to extract the airbox(disection is fastest!).The location issue for the air filter is addressed by the suggestions at the beginning of this post.