help me I just bought an 84 300T need tech help

[solson96]

bought this off ebay and the seller states,"
the transmission began to slip slightly in first gear. I determined that the transmission fluid was a little low, so I decided to try and change it out. I got a new filter and gasket, but couldn't get the car but barely high enough to get under it. I had to stretch to drop the pan, and when I went to reinstall it, I apparently didn't get the gasket on right. I took it out for a test drive, and it still slipped a little in first gear, but not as bad. However, when I got it back to the house, transmission fluid was pouring out from the bottom of the car around the pan. So, whoever buys this car is welcome to bring your tools and jack(s), drop the pan, and install the gasket correctly. (The gasket is made of hard rubber, and I don't know if I damaged it or not).

What do you think it is, does it sound like it needs a tranni overhaul or just something, ie maybe he really is mechanically inept.