Very nice I did something similar last year but I wanted to still run old school tube tires so I got 1 piece drop centers from Coker 4.5" rims removed my old centers and welded them into the new blank...
Like you said seemed easy in concept... I too had to turn down the centers, I didn't have acces to a lathe big enough either... I went with a rotary table on a bridge port ...
Here's my process it's funny how similar we went about it..
https://www.stovebolt.com/ubbthreads/ubbthreads.php?ubb=showflat&Number=725349&page=1
