I have done it several times with the older 0-6-0's my Durango and silverton is one of my favorite steam locos nets to the red and blacks and my UP FEF

i model a lot of european and i has some of the brawa rigid couplers for nem "Brawa Rigid Coupling
Item no. 2250"

For a lot of my rolling stocks that is british i buy from http://www.ajmrailways.com/
She is fast and reliable... takes only a week to get of my city in rural california. and she has qutie a good supply.
i will warn you all her prices are in Australian dollars but it end up alot cheaper for us.

i have 4x NWSL 2800-6
Bachmann spectrum 80 ton 3-truck shay #81907 regearing kit

If you ask really nicely i work at a hobby store that still has them

i have an 0-6-0  that its minimum radius is 9 inches

! off My friends kis is very autistic, so a loco with a large amounts of details is pointless. and a z scale motor may work just get one with a 1.5-2 amp peak. I have percy with sound in
https://www.youtube.com/watch?v=lgSiO9UzJKU

they make a very rare appearance in the us market... i have  bought a few... Greg/Percy and Lner #7 i bought for me... most of my buy were for my friend's autistic kid. He didn't want a face on the locos

Only the Bachmann Junior were dcc/dcc ready. they used the same chassis... but installing dcc is really easy and only takes about 15 min depending on the decoder you want to install... sound about 45

Well i still have 4 packs of them in HO

The Way NMRA  8 pin plugs are designed no damage will occur

NWSL sells a regearing kit http://shop.osorail.com/product.sc?productId=1935&categoryId=-1
my store also carries them

http://hoseeker.net/ has maintance diagrams
and who makes is Rivarossi, life like, Etc, pictures would help to

I have started using Esu, there is a nice guy that sold me one with thomas actually talking on it, gave it to my friends kid as a birthday present

https://www.youtube.com/watch?v=s5gjWpbuZVg /here Mavis and i like to work on the ground because of my back i messed it up big time(But that is another story)