My G/F suffers from arthritis and has half her left hand amputated. She shoots a S&W 642 with a Crimson Trace. Her shape allows the use of an OWB belt holster on her strong side, but most of the time she prefers a fanny pack. We tried a bunch before finding the Tommy's Gun Pack.
http://www.tommysgunpack.com/Product...?ProductCode=1 It's opening is much easier for her to use than any others, and it's not expensive to try out. She also is comfortable with a cross-draw, and that would fulfill your need for driving access. It'd be nice if everyone could just send you one to try out. I'd like to see some holstermakers voice their opinions for this new member. Her problems are not rare! Welcome to the forum!!!