Qapla'!!!
Through the precision efforts of scattershot repairs, including but not limited to: New coil, cleaned ISCV, new spark plugs, reset timing, and a fully armed and operational CEL 54 defeater, my Alltrac...err excuse me, "Turbo 4WD" Celica starts and idles smooth as a purring kitten. Adjusting for gauge calibration I read about 15 inches of vacuum at 1200 idle while cold. Might still have a vacuum leak somewhere but I can worry about that later, finally.