Forum:Equip cards on Obelisk

I was wondering, can I equip Equip Spell Cards to Obelisk the Tormentor (Effect Monster) while he's face-up an the field? Also can I use a card that Equip cards that eqip to him while he's in the graveyard or removed from play (Premature Burial/D.D.R. - Different Dimension Reincarnation)?