I have a Mantua 2-6-6-2 T DCC ready . It uses a nine pin plug I could sure use some suggestions as to the easiest way to install a decoder; and no instructions as to how to take the loco apart to install the decoder. I have a TCS DP5K and a Bachman 1amp decoder.
Don ???
Do either of the two decoders you have terminate with an 8 pin plug? If so, you will probably have to cut it off. The connector on your loco is a "female" JST 9 pin, so you need a "male" JST on your decoder.
Litchfield sells a male JST connector you can solder onto either decoder's wires, then plug into your loco. If you don't want to cut the plug off your decoder(s) then you have to make a harness with male JST on one end, female 8 pin on the other.
As far as I know, no one makes an adapter harness with female 8 pin plug on one end and male JST on the other, you have to make your own.
Of course, the easiest way is to install a DH123 which has the male JST connector. :D
I was pleased to discover my AC4400s came factory wired with both the female JST and female 8 pin, giving me a choice of decoders.