I've got a local tranny shop to replace them and check the front pump. Previous owner did not hook up oil lines to the radiator and plugged the ports with bolts. Pretty sure that blew the front seal around the torque converter. I have it plumbed correct now.
Shifts good. Just leaks.
Plugged cooler lines would not "blow the front seal"..... plugged cooler lines cause far more serious damage.
On the C6, the front port is "OUT" to the cooler and the rear port is "IN" from the cooler.
The rear port return line from the cooler feeds the lubrication circuit inside the trans. IMPORTANT!!!!
It lubes the sprag clutch and planetary gears.
If there is no oil flow into that rear port,
very serious hard part damage can and will happen if the car is driven any significant distance.
Case in point.
Years ago I built a C6 for a friends 67 Mustang GT 390.
When he re-installed the trans he kinked the rear cooler line so badly it stopped oil flow into that lube circuit. (basically the same as plugging the ports)
(also he had headers on the car and the tight fit of the headers made it hard to get the cooler lines hooked up, so he "mangled them" into place
He drove the car about a week and then took it to the 1/4 mile track.
Shortly after that the trans failed.
When we got the trans apart the sprag was destroyed along with the case bushings and sun gear bushings.
He's lucky the planets didn't fail.
Good on you for hooking up the cooler line properly
...and hopefully the previous doofus that plugged the ports didn't drive the car much with them plugged.
In any case... your leaks have not been caused by the plugged ports.
Something else is going on and it may just be a matter of replacing some seals..... OR...
The bad news is, the previous doofus drove the car far enough with the ports plugged
that there is the beginning of hard part damage and metal particle contamination in the oil that is damaging seals and causing leaks.
Hope it's not that...
You say it shifts good... so there is hope no significant damage has occurred.
PS, I'm a transmission re builder with over 45 years experience so I might know 1 or 2 things about automatic transmissions.