Welcome to the wonderful world of GMAT, travelerbk! I'm engaged to a recent law school graduate, and I suspect that you're making a really really great decision by switching to the GMAT. Law school was not fun for anybody involved.
As usual, bb is correct about the benefits of the LSAT: you won't have too much trouble with CR and RC, though it wouldn't hurt to keep your skills sharp in those areas. You also won't have any timing problems on the verbal section. The LSAT is waaaaaaaaay more time pressured than the GMAT verbal section, so if you can get into the 170s on the LSAT, you'll have time to spare on the GMAT verbal.
For whatever it's worth, it's good that you won't have to spend tons and tons of time on CR and RC. For some people, those are the most difficult question types to improve, since they're reasonably pure tests of your reading precision. You're way ahead of the game if you have those mostly locked down already. You can definitely make some big gains in quant and sentence correction if you work hard enough, so you're in a pretty good spot, especially since you have a finance background and math isn't exactly a foreign language for you.
LSAT logic games aren't very helpful, unfortunately. They definitely won't help you on the quant section, but they'll give you a tiny edge on the Integrated Reasoning section--a few of the questions are vaguely similar to the LSAT logic games. Integrated Reasoning isn't a huge part of admissions decisions yet, but at least your LSAT background will allow you to conserve a few brain cells when you do the Integrated Reasoning on the GMAT.
Good luck with your studies!
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