I would not attempt to do this without the proper engine stand. I'm sure that someone on the board would be willing to lend or at least rent you the tools (it's the same stand for all 911s) - you need a generic engine stand and the 'holding fixture' - P201, part number 000.721.201.00, which plugs into the stand. The holding fixture is $230 from our host (
http://www.pelicanparts.com/catalog/shopcart/ptoo/POR_PTOO_miscel_pg1.htm), and then there's the cost of the stand (or the bench clamp thing, but I don't like the looks of that). If you really wanted to and were very careful then yes, I'm sure you could do without the stand - but like I say, I wouldn't. The amount of damage that could potentially be done to your engine means it just isn't worth it IMO
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The combination of the undertray and the southern California heat probably hasn't done the engine any favours. You may want to (well, need to) replace your valve guides. You could also check for leaks around the (infamous) cylinder heads.
I've sent you a PM, by the way.
edit: clarity