Hi!
My apologies for the long delay in replying! I was getting an e-mail every time someone posted here, but that apparently quit working - Sorry!
The 6.4L is an easy install. The oil pressure feed to the bypass filter is via a replacement billet oil filter cap that replaces the factory part. This cap has a port in it to accept the pressure line. The filtered oil is returned to the oil pan through a special drain plug that replaces the factory drain plug. Other than attaching and running these two lines, the only task is to mount the filter unit itself to the frame rail which involves drilling two holes. I would say on average for a first time install, it would take 1 - 2 hours.
Please let me know if you have any other questions - I do check e-mail - usually about every 30 minutes, so I will get back to you fast!
Tim