Nice truck Digg
Working alone I install mine a piece at a time.
very enjoyable... it starts to look like a truck again.
steps 1-11 here
http://chevy.oldcarmanualproject.com/shop/1948_51truck/51ctsm0103.htmwill help with front end alignment.
Did you remove your cab?
fender brace dimensions here
http://chevy.oldcarmanualproject.com/shop/1948_51truck/51ctsm1105.htmI ended up needing shims under the rad support.
Very good advise given above to leave all fastenser loose.
Do you have any more pics?
Good Luck