[72LuxuryLeMansLa.]

I have, what I believe to be the original th350 in my '72 Luxury LeMans and it has started slipping when taking off. It slips in 1st gear only, not from 1st to 2nd or 2nd to 3rd. It started by slipping for a brief moment when I eased on the gas one morning when it had not been driven for three or four days and I chalked it up as a fluke. Lately it seems as though every time I get in and go, in weather below 55*F, for the first run of the day, it slips for a few seconds. The fluid level is good and it smelled normal a few days ago when I last checked it. I've only had this car for two years and 30,000 miles and it isn't raced. It mostly gets highway driving at between 60 and 75mph. Any ideas or experience with this? Tranny or torque converter?

Thanks,
Karl