Mohammad Hafeez (11) and Younis Khan (10) were at the crease when the umpires ended play 18 overs early due to bad light.
Gul and Shahid Nazir (3-42) exploited the conditions beautifully after Brian Lara chose to bat first in the West Indies first test in Pakistan in nine years.
He was the only one to battle successfully on a seaming but slow pitch, making 61, and West Indies were bowled out in 56.1 overs shortly before tea after two collapses.
In the morning the visitors lost four wickets for 11 after an opening stand of 41 and then in the second session their last four wickets for 32.
Lara returned to form with a fighting half century, recording his highest score in Pakistan at the same venue where he made his debut 16 years ago.
The left hander showed touches of his pomp and power with eight fours after a nervous start when he survived two confident appeals from Nazir on his first three balls.
Opener Chris Gayle (34) was in imperious form, hitting six fours in his 28-ball innings before he was unlucky to be given out to Nazir, hit high on his thigh pad.
Dwayne Bravo (32), who hit five fours, drove leg spinner Danish Kaneria straight to Nazir at mid-off after putting on 44 with his captain.
REUTERS HSB BD1752