Hey Gary - what follows are pictures of some bleach successes and one major disaster (the only one I've had). Two pennants had orange ink and were fine. The 1962 pennant has magic marker on it and a terrible tip but I don't think I've seen another in white. Two had blue and they were also fine. The red was a disaster. I drew the graphics back in with a sharpie and gave the damn thing away.
I always tape off the spine and hang them vertically on my shower wall. Spray with bleach and saturate with clean water very shortly after (a matter of seconds). Some other guys use 20%, 40% or 60% bleach to water for the initial spray. I have always used straight bleach but a watered down solution is probably a good idea.
If it were me, I'd try the Tigers pennant because I've done OK with orange. I think the red ink on the Yankees would rule it out. It's too bad because that pennant could really use a good cleaning!