AT Front Seal - DIY Job?

Hello all,
My '91 300E (192K Km) I changed my ATF, filter and pan gasket a couple weeks ago and everything was fine, car shifted nicely... a little better in fact. Anyways, a couple days ago I started to experiance really rough shifting and "flare". This afternoon I was explaining this to my friend and he replied; " Hmm, that might have something to do with the puddle of oil you left in my driveway 2 nights ago." OH-OH! A quick look under the car confirmed that it was indead an ATF leak.

I drove the car to a Rent-A-Bay this evening and put it on the hoist. I noticed that ATF is leaking from where the transmision mates to the engine. The mechanic on duty seems fairly confident the front seal is the culprit. He also explained that its' not uncommon for these seals to leak after a fluid change, the old ATF being thicker than the new + old seal = leak. Comments?

Is replacing the front seal a DIY job? I've read in the archives this is a 9 hour billable job at the dealership.My skills as a DIY'er are mid level and I have no reservations about tackeling this job. Recommendations? Advice?

Cheers for now
EADG
91 300E