 Here's some info on head gasket replacement:
Yeah, well it's pretty much the same for all head gaskets. I have not done it on an LTD but it too, will be the same. To remove the head gaskets, you have to remove the heads. And everything pretty much, that is attached to the heads like carburetor, intake manifold, exhaust manifold etc. And you have to remove anything that is attached to brackets that are attached to the heads, like the Air Conditioning compressor, alternator etc., or at least loosen them and swing them out of the way. To find WHICH head gasket in a V6 is blown, do a compression test and look for two (or more) cylinders that read really low, like way under 100 lbs. The rest of the cylinders will probably read up around 140 to 170 lbs. Becaue a V6 and a V8 have two heads, each head has a head gasket so there are two head gaskets total. You COULD just replace the one side that is blown but that would be pretty stupid, as it is labor intensive job, and wouldn't you feel stupid to spend several looong weekends replacing one head gasket and then reassembling the entire upper end of the engine, only to have the other one blow a few weeks later? AND, while you are at it, it's a good time to have a machine shop, or at least a competent mechanic examine the heads to make sure the valve guides look OK, and the valves looks good too. Becasue if the heads need any machine shop work NOW is the time to do it, or again, you get to redo all the work all over again when it becomes obvious any work is needed.
Take TONS of digital camera pics from every conceivable angle during each stage of the job so you can tell how it all goes back together. If you don't you will wish you had. I am not sure changing a head gasket is the first repair job I'd wish on a novice, although it is certainly do-able with a good manual, some knowledgable friends and if you have a good selection of tools and are fairly handy repairing things already.
Now - don't get me wrong, it's NOT particularly a HARD job, but it does take a LOT of time to remove all the stuff on top of the engine and then replace it all back where it was, and because it takes a lot of time is why the repair shops charge about $1000 or so to do it. Let us know here on the fourm if you try it and how it all goes, and we will be happy to help with whatever info and advice we can provide! | 
