Clutch Slippage and Shaft Seal Replacement

It's been a while since I've been on here, I've put about 250 hours on my Farmpro 2430 since my last repair but now I'm having an issue with my clutch, the clutch is slipping when I pull my ground engaging equipment in High Range first gear or higher. I opened up the inspection window and the entire clutch pack is covered with gear oil. I also have a small amount of gear oil under the clutch housing of the tractor where it's parked. I was thinking the gear oil is getting on the clutch and causing my slippage so I used a ratchet strap to hold my clutch pedal down and cleaned the clutch and pressure plate with brake cleaner. Went back to work and this solved the problem for about an hour, but now it's slipping again. I'm assuming there must be an oil seal on the final drive shaft and/or the PTO shaft between the gear box where the gear oil is and the clutch housing. I know I will have to split the tractor, but can someone tell me what else I'm looking at doing to replace the seal/seals? I'm just trying to figure out how much time to budget for fixing it. Thanks.