The explorer intake and the tubular GT40 both fit under the stock hood. I had to dremel one of the braces to make room for one of the bolts but that was about it.
Don't forget that you will need to re-configure a lot of your vacuum lines with the new intake and plug some holes. Also, if you plan to keep your EGR valve, expect to have deal with the bung and pipe not fitting together quite right.
The GT-40 was a lot of work for no noticeable power gain on the stock heads.