Torque converter weights

Can the weights be bought and welded onto the torque converter while it's in the car? It just so happens that I didn't know it at the time but the converter the transmission guy bought for me isn't balanced for my 360. I never checked or noticed before putting in, now I would rather not remove of I don't have to
Back in the day they where available and came with a templet to help install in the exact spot.I would check with a Mopar Performance dealer, such as Mancini Racing.