I'm no expert on soldering, but all my soldering problems evaporated when I bought a decent soldering station. Cheap soldering irons are pure trash. The guns can be useful for inaccurate stuff, but for precise work spend $50 and you'll be glad you did.

This one will work for you. I've had another of their stations for close to 10 years with many many hours of use on it.

Then get some 63/37 solder (as thin as possible for you application, 28 gauge preferable). I'd check that circuitspecialists site, but then I'd probly also check ebay.

Then watch some videos on youtube about SMD soldering.

 

So I have both my FOBs and both work, but one is missing the plastic over each button and the other is missing the plastic button over the lock only. Is it fairly simple to just order 2 new key shells and swap off the two shells on the existing keys?

 

It's very simple to do. Here are some options on ebay.
land rover key fob | eBay

Look for the DII Fobs. That link lists D3 D4 etc...

 

Ordered and done! Glad ya'll elaborated. I was thinking I had to drop $150 plus on re-coded keys just because my buttons fell off. I bet many folks don't know about just replacing the cases.

Thanks!