Cub 2135 (1996) Kohler 12.5 hp OHV - small Oil leak underneath center of tractor

Hi everyone,
After mowing last night I put my Cub inside and noticed a bit of oil on the concrete where I stopped the tractor prior to driving it into garage - about a couple of thimble-fulls spread out in 2 distinct locations. I checked the area around the oil filter and oil drain plug and found no oil leaking. I put a piece of cardboard underneath and on checking later found 2 separate locations where oil had continued to drip for a short while after I parked it. Oil stain location on the cardboard was about dead center below/behind where the PTO assembly is and another small amount to the left of that (opposite the oil filter/drain plug on this tractor). There didn't appear to be any continuous oil drops from the point where I had parked the tractor before driving into the garage.

I checked the oil as well and found it low but still on the dip stick in the safe zone; engine was running fine up to the point I parked and turned if Off.

I wasn't able to look at it last night but I'm now suspecting the Front Engine Seal is leaking and was hoping to get some advice from the DIY Pros here.

1. If it is a front engine seal, is this something a DIY'er would want to try?
2. What is the estimated cost for the parts needed and should any other repair parts be included for replacing when the front engine seal is replaced?
3. Do the parts for this come as some part of seal replacement repair kit?
4. Any special tools needed for this job?
5. About how much would this job cost to have a Cub Repair shop do it?

Thanks for your help,
greynold99

I found a post related to mine by Poravec who asked for information about replacing the Front Oil Seal in April 2015, I think it's in the Small Engines - Kohler forum here...

He was offered the advice to also replace the following:
1. Output Shaft Seal
2. Oil pump gasket
3. O-ring to the oil dipstick tube.

Rivets, who I've read posts here before on Cub Cadets - suggested he clean out the '... Oil Return Port.' - but I couldn't tell exactly where that was to be done.

Also the posts suggested that pulling the engine was the easiest way to get to everything needing accessed.

I'm hoping Poravec and some of the original respondents might pick up on my questions.
Thanks again,
greynold99