BT - there has been lots of good advice in this thread, most directed at postponing the truck until after the wedding.
There are 3 "rules of thumb" of which I am aware in the old car (truck) hobby:
(1) Get a consensus of cost from those in the business. MULTIPLY BY 3!!!
(2) Get a consensus of time from those in the business. MULTIPLY BY 4!!!
(3) Never (that's right, I used the word "never") set a deadline to have it finished.
Go to your bride-to-be and inform her that you would rather spend the next nine months helping her to plan the perfect wedding than work on the truck; and that you can work on the truck later.
Jon (old car, truck, and tractor nut for 50 years; happy husband for 41 years).