hi, cant give you any info about a 4 stroke, but I can about the model.
first off the book CofG is WRONG, set it at a MAX of 130mm back from the centre join of the wing, 120 would be even better. that is where I have mine.
I have the ESM P-51B model, with an RCG26 in it, in hindsight I wish I had put the DLE 30 in, but it flies well with the 26, this model looks great in the air and on the ground, there are a lot of D models around, but not that many B models.
the other thing is beef up the undercarriage mounts, then tilt them forward as far as you can, have the back mount almost level with the wing, it will improve ground handling a LOT. the balsa on the L/E where the wing locating pins glue in was very soft on mine, they came loose, with the balsa still stuck to them, I put longer dowels in and made up brackets to hold them in place.
there are a couple of threads to have a read of,
http://www.rcgroups.com/forums/showthread.php?t=1141908 ....
http://www.rcuniverse.com/forum/m_93...tm.htm#9371367 ...
http://www.rcuniverse.com/forum/m_93..._1/key_/tm.htm so you have a bit of light reading ahead.
the book control throws for elevators are also out of dream land, ailerons are reasonable, but be careful of the elevators, I think I have about 10mm up.
Oldtimer