I honestly cant point you in the right direction. I'm sure you will find someone who can do it and perhaps save a few quid. But I would suggest you reconsider this r tech outfit, these guys have it down pat. I bet I will have at least 20k in parts alone on my little s.w.b. updates, and I would venture to guess many hundreds of hours, 4 dozen bandages, 35 or more 3 day backaches, you get the point. Then comes paint work...another $1000. in materials... tear it all down after the major bugs have been sorted out and spend another couple of hundred hours and hope I can make it look satisfactory.
My point is this. I think you'd be happier in the long run with the real McCoy. I looked at their truck called the "Duke" and for 75k, its a fair price.
Just my 2 sense. lol