I found this site for B-17's with 100 or more missions
At the start of the operations, it was remarkable to see a B-17 Flying Fortress complete 25 and later 35 missions. The B-17 Flying Fortresses of the following list prove that they can be more than 100 missions. These B-17s have flown at least 100 missions and known as Century Bomber. This list...
b17flyingfortress.de
As for B-26's I have the following incomplete list sourced from various sites and Books in my possesion
Flack Bait B-26 202 Missions
Hells's Belle II, 12AF 1st B-26 to complete 100 missions (May 1st 1944) in the ETO, total missions unknown (to me)
Mild and Bitter 12AF 2nd to 100 missions total unknown.
Big Ass Bird reached 100 on 6th June 1944 S/N 41-34938 total 145.
Zero-4 reached 100 missions on 11th June 1944 S/N 41-34868 total 148.
O'Rileys Daughter SN 42-107550 reached a total of 165 missions
Idiot's Delight 320 BG 100+ Missions.
Jersey Bouncer III 17BG 100+ Missions, shot down on its 130th mission.
Mean Young Un 443 BG 163 total missions,
Old Iron Sides 17 BG 164 total missions.
Half & Half 320th bomb group had a very interesting carreer it flew 160 Missions with that name, its front 1/2 originally flew as Goatee Hell flew a unknown number of missions before its tail section was damaged in a landing accedent, it had a salvaged tail section from anouther B-26 added and renamed Half & Half, finished 134 Mission in this configuration, It again had it tail section damaged (no info on how it was damaged) had anouther tail section added and finished 26 more missions to bring its total to 160?
In addition the following B-26's almost made it to 100 Missions
Sweet Sue Crashed on TO on its 95th Mission all crew members KIA.
Duration Plus Crashed on T/O on its 99th Mission, all crew members survived.