I was thinking the same thing
All springs had the + sign painted on and looked to be identical.
I dont think the OME front springs on my YJ are shimmed.
Although mine are the medium duty springs.
You can disregard the +/0 markings on the springs. According to ARB, they are only used during the manufacturing process, to indicate whether the springs were manufactured according to spec (0) or slighty better (+). They said there are no differences between the + or 0 springs in terms of lift, spring rate, or installation. As long as they are the same part #, it would not matter if they were marked + or o.
On a side note: I love my OME lift! It rides great! You will be happy you went with OME!
1992 YJ -2.5 Old Man Emu lift, RC 1-1/4" Boom greasable shackles, JKS Discos, 1" Daystar BL, 33x12.5x15 BFG AT KO's mounted on 15x8 Cragar soft 8's, flush mounted tailights, SJFab front bumper, TKH Fab swingout tire carrier welded to a Dirtworx rear bumper, Tuffy stereo console, RC SS Extended brake lines, Home brew plate relocation bracket, Magnaflow Cat, Dynomax Cat back, No track bars front or rear
1997 XJ - 4.5 RC coils + extra OEM spring isolator(6.5" actual front), OME medium duty springs+OME extra leaf + Teraflex 1.5 shackles (6.5" actual in rear), OME Long travel shocks, OME SS, IRO Adj TB, IRO Adj LCA'S, IRO Adj Uppers, RC Control arm drop brackets, JKS Quicker Discos, SYE / XJ shaft, 33x12.5x15 BFG AT KO's on 15x8 Cragar soft 8's, RC SS extended Brake lines, Hella 500's
1996 ZJ - RE 2 inch BB w/shocks (rides like crap), OME SS, 31x10.5x15 General Grabber AT2's - SOLD