PH Front Springs

[MBF]

I've looked through the forum, done a search, and looked at the technical references.   I'm replacing the front shackles on my 1 ton and have also installed the rear brackets from a parts truck as mine were badly worn.  I don't have the shackles yet (bought from ESPO Springs and Things) but both of the brackets that I installed from the other truck appeared original, and were both right hand threaded for the bushing.  I looked up the bracket p/n in my parts book, and that shows only 1 p/n (13-53-17) so I assume that they're both rh threaded.   The shackles are left and right so I assume from reading the old threads that the lh threaded bushing goes into the spring eye of the driver's side spring.

 

My next question is installing them.  The factory svc manual says to install the bushings until there is a 3/4" gap between the shackle and edge of spring, and upper shackle and edge of mount.  How tight are these bushings supposed to be, or do I just tighten them until I reach the recommended gap.   I did this process about 10 yrs ago w/o replacing the worn mounts.  I want to make sure I do it correctly this time.   Thanks.  Mike