yeah, that shudder is such a pain. When I worked for a bus company, we ordered 6 new 1996 Ford vans for a limo-type service. 4 of the 6 had that shudder from new. The other two developed the shudder within 70k
It doesn't seem to hurt much, so we just kept on driving them. I left the company when they all had about 200k on them still running just fine... but annoying with that shudder.
You might be able to get them to replace the TC and see if you get a slightly better one this time, but its up to you.
Congrats, buddy. Doesn't it feel great to have a new tranny?