All of the TCS decoder will runt he same, other than shape and number of functions they are essentiall all identical. I use only TCS decoders because I love their performance.
Me, I'd just install a T1 and wireit in place. Remove the light board in the loco. Repalce the bulb with a golden white LED and a 1K resistor. I remove factory boards in most every case so as to not have to deal with anyy oddities or possible defects that don;t make a difference on DC but could fry a decoder. It's pretty eacy on those locos, because the wires are all in a physical location that makes it obvious whch wire goes where - left and right rail pickups, motor leads, etc. Plus a basic T1 with a bare wire harness is the cheapest option. Only thing cheaper is the T1A with no harness at all - perfect for those locos with a 9 pin plug.
--Randy
Modeling the Reading Railroad in the 1950's
Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.
Up to now 8 out of my 13 locomotives have been converted to DCC. Most of them have been made by a technician at a LHS but I made the last two with success : a DP2X-UK in a Bachmann Spectrum 2-8-0 and a DH123 in a Bachmann Spectrum 4-6-0. Both installation have been a breeze but I don't like the low speed control on the 4-6-0 so I will change the decoder for a TCS T1 pretty soon and I won't buy a Digitrax decoder anymore.
My next project is a pair of Proto 1000 F3 A-B. those locomotives are DCC ready with a 8 pins plug installed. On TCS site they show the installation of the DP2X-UK but recommend the LL8. Someone told me that the T1 would be a good choice. As I don't need 8 functions for the F3A which has only a front light, I think I should skip the LL8 but I am not sure.
Guy
Modeling CNR in the 50's