Can you please elaborate on the spacers...? Are you talking bout wheel spacers? Thanks
If you remove the dust shields then you will have a gap when putting your Hub back together. I don't think this is a really big deal but I didn't want to take that chance. They are technically call Back Plate Eliminators.

https://www.trail-gear.com/TG/Backing_Plate_Eliminator_Kit/i_0_0_/_140058-1-KIT.aspx#.Vyo1ifkrJpg