My deepest condolences seb for all your mates and his family too. Loosing loved ones is never easy.

As for the Ute IM sure most members would pitch In something. In all honesty not to be harsh, I've seen people do this kind of thing before, and once its done it just sits there doing nothing. The intentions are great but id hate for all his friends and parents to go through the build and not feel excited or that sense of closure at the end,of it.
Also if money is an issue there's the upkeep of the Ute,later on that may become a Burdon and if the Ute ever had to be sold you all may love through the pain of loosing that,last physical reminder of him.

Things to consider but once again I really do feel for you. I lost someone tragically earlier this year. Maybe not best mates but we were becoming good friends from work. And every day there's a reminder when I sit at my desk and he's not there as well.