Overdrive tranny in an A-body

I've only had mine up and running for a few weeks, then had to put her back on stands to address an oil leak, and then got into doing a little work on my exhaust, and then it's been snowing a lot for a couple weeks.
Point is I've only had it out for a few drives, but it seems at this point that I don't have any drive line vibrations at all, or at least not that I can feel. I've only had it up to 65, and haven't done any hard acceleration take offs yet, don't know if there will be any issues when putting more torque to the rear end and it rotates a bit. Right now it all seems fine.
But I gotta say the overdrive is awesome, and well worth the effort.

For the guy that mentioned the Gearvendors unit, you'll probably have about $3500 bucks in that setup by the time your finished. You'll have I think its a .78 overdrive instead of a .69 like the A500. I have less than $1000 in my A500, that's the trans, some clutches/steels, gaskets, seals, the USCartool crossmember, and driveshaft shortening. The A500 also gives you a lockup converter, and a lower 1st and 2nd gear (compared to a 904).