lower control arm install ?

[my67chevytruck]

hello, after we did the 72 crossmember swap into the 67 , we blew it apart to rebuild, and install ece drop spindles. The question i have is how do you center the lca on the crossmember, i had rough measurements from the ubolts to the lca front and back on driver and passenger side but these were accidentally thrown away when we cleaned the garage. i have the lca's loosely installed, do i go ahead and install the spindle loosely and let it dictate the centerpoint via the balljoint shaft? the tighten the lca and install the spring and spindle completely? Thanks for any suggestions.