I've taken L-tryptophan for its own sake (it's a serotonin precursor), but never for SSRI withdrawal. I have friends who have taken it for SSRI withdrawal to good effect.

I would start out by buying a good pill splitter if you don't have one already. You should be able to split the 100 mg into fourths, right? Then I would try a week of alternating 100, 75, 100, 75...then a week of all 75...and so forth. This is what I've done successfully with Effexor.

Good luck! Keep us posted.