I know its not the exact same. Its close though.
My 66 Coronet weighs 3480 with me in it ( i weigh 260 ) before I add weight to move it to an index. It has a glass hood, bumpers and deck lid. The 1/4 glass in mine is lexan due to a mechanism breaking. So I pulled them out. All the rest is factory glass that rolls up and down. Mine at the time of scaling was a stock block 499 with aluminum heads. It is a NSS car. So it has 2 seats, carpet, headliner and a full factory dash. It has a cm 12 pt cage and ladder bars.
Surely you can get a same era belvedere to the same weight.