I have a 1980(ish) Sunset Models N&W J Class 4-8-4. It is all original (right now) and I need to convert it from 2 rail operation to 3 rail. I have found a company that will install MTH ProtoSound 3 in it, but I was wondering work I need to do to prepare it for that. For the wheels I am using Lionel's parts for their recent rendition of the 611. Obviously I will need to install pickup rollers, but should I also use the Lionel motor or is there a better option? Also, are there any other steps I am missing? Thanks!