RU.08 said:
I think it was the 1997 version. Before that my understanding is they just scanned the o-negs in Telecines to produce the SD outputs for TV/Laserdisc/VHS. The negatives were cleaned for the 1993 transfers, I don't know if that qualifies them as "restorations" though.
In any case, new theatrical prints were struck for the 1997 SE.
I'm pretty sure IPs were used for all pre-97 releases.