[msmith10]

I'm considering a changeover to a Lithium battery system. I currently have 2 Trojan T125 deep cycle 12 V batteries (12V golf cart, somewhere around 200 amp hrs combined) with shore power to an old charger which I'll need to replace going to Lithium. No separate starting battery. 55 amp Mando alternator with internal regulation (from Moyer).
My average use is about 5-7 amps/hr for autopilot, instruments, radio, AIS; lighting is all LED, and for most of my sails I have way more than enough power. However, do 1 or 2 long distance (300 miles) singlehanded races each summer. I really can't cut down much on my power consumption during these. I converted to an icebox rather than refrigeration which helped, but the autopilot is a necessity and that's by far my largest power drain.
During those races I can't avoid running the deep cycle batteries down to 12 volts and sometimes a little less before I can charge them off the engine (in neutral, of course). I usually have to charge about 1 hour every 4 hours or so after the first day to keep the batteries above 12 volts, but obviously this really stresses the batteries and really limits my power. Alternate charging (wind, towed generator) is not an option and I think Lithium would be my best solution as it would allow me to drain much lower and charge much faster. Lithium batteries are becoming much more affordable, and considering my Trojans last only 3-4 seasons, the payback could be pretty quick. And I could get rid of 100+ pounds of weight, and with smaller batteries which weren't positional, get that weight a lot lower in the boat.
The questions I have for this esteemed group are:
Other than a shore-power charger made for lithium, what other components do I need? Battery monitoring? Do I need to change the regulator on the Mando? Should I have a small lead acid starting battery (lawnmower type), and if so, can I tie it into the charging system easily?
Can anyone recommend a good guide/ book that would address these issues and any I haven't thought of?
I have time to study the problem as I'm not doing it until my current set of Trojans is shot, but I want to know what I'm going to do ahead of time.