I always like to do at least 2 exercises per body part. But if you're going 3x8, the volume will be pretty low, so you'll want to hit the body parts more often.
I've gone back to 4x8 to 5x6 (depending on exercise) 3 exercises per body part, plus a supersetted additional exercise.
i.e. Tuesday I did:
Flat bench (8x80, 8x100, 5x120, 4x130, 2x140 DS: 12x80)
Incline DB bench (8x20, 8x25, 8x27.5, 8x30, 6x30) // flies (5x8x15kg)
Dips (8xBW, 8xBW+10, 8xBW+15, 8xBW+20, 6xBW+25)
BB curls (4x8x30kg) // Alternating DB curls (4x8x15kg)
Wednesday:
Chins (6xBW, 6xBW+5, 5xBW+10, 5xBW+10, 7xBW)
T-Bar rows (8x40+bar, 8x80+bar, 8x100+bar, 8x120+bar, 10x80+bar)
BORs (10x60, 8x80, 8x90, 8x100, 8x100)
Seated EZ bar french press (4x8x27.5kg) // Cable tricep pull down (4x8x70kg)
Those 2 sessions so far in spite of having done AGVT have left me in pain. Short pauses, slow negs and decent weights really start to get the body going!