You might have to remove the chain case assembly to be able to get it out though.(which then means gotta remove the passenger side engine mount) When installing the new seal, put a little oil on the outside edge of the seal (that contacts the chain case assembly) and a little oil on the inside of the seal (that contacts the crankshaft). The seal will be right there under the pulley. It should be as simple as: drain oil, remove front bumper under-tray, remove serpentine belt, remove crankshaft pulley. It would be fairly easy to replace, depending on your mechanical skills. #6 in the link Jesbecause linked to is the front main seal. I ain't trying to sell this thing - I'm just providing my own personal are correct, there is a front main seal, and a rear main seal for the crankshaft. Wasn't expecting to do one but I had the pics so here y'all go. I'm usually caught up in the labor and under the gun as the 2 year old nap schedule is all I have time-wise. I'm not very good at write-ups so I hope this comes out ok. They have an amber option for lighting and an optional antenna mount. If you're interested in purchasing one get ready to fork out some cash.

I used some clear automotive RTV around the nutserts for additional leak protection. This actually appeals to me as I am tired of messing with the little 10mm nuts holding the shabby housings of the stock style lights. It requires (4) 19/56' holes and nutserts so you'll need one of those tools too. If drilling into your cab makes you queasy you'll steer clear of this product lol. Didn't wanna mess with another switch installation! After several cheap lame (leaky) lighting choices, I went for the best (and most Designs lighting is on point, as usual, and I hooked it up to a remote so I can use them without a switch. It is heavy duty quality with a thick rubber tube gasket all the way around so I don't expect any leaks. Finally got my truck back from a rear main seal fix so decided to knock out the 3rd taillight replacement from Evil Manufacturing.

Seal of Evil instal