As you surely know, Principia makes Trans-Lunar Injections much more difficult than the stock physics - because of the nodal precession. Moon's inclination varies between 18.134° and 28.725°.

There are basically three options for an efficient TLI from a higher latitude (ie not from the French launch site in Kourou):

• If you launch from Cape Canaveral around the Apollo 11 mission - during 1969's Major Lunar Standstill - the Moon is almost perfectly aligned and nothing is needed except to launch into the right LAN - you can launch every day
• In all other cases one must do what some call a Baikonur-style launch - wait until the Moon is 51° before its AN or DN - then launch into its LAN - add 4 days for a Hohmann transfer - the Moon advances 51° - and you will intercept it right at its AN/DN - in this case you have two launch windows per draconic month
• The Russians launched some of their very early probes from a polar orbit - which allows to launch from any latitude every day, but this is a very hard launch as you have to time your position along the orbit

Normally the second launch should be doable with MechJeb - except I can't find any information window that has what I need - either the time or the angle of the Moon relative to its AN/DN relative to the equator. Am I missing something? I am willing to submit a PR, but I want to make sure that this is not possible before investing time.