The MP eight wheeler is the MP mogul with the wheel arrangement changed. If you will examine the sanding lines, they are all wrong for an eight wheeler. IHC issued almost the same locomotive in HO as both the mogul and the eight wheeler, although the prototype on which both are based is the mogul. By all reports, the IHC product was pretty good. The MP product left a little to be desired.
The MP mogul is loosely based on an SP Harriman mogul. None of the cabs offered with either the mogul or eight wheeler are correct for SP: one is an ALCo cab, the other an arched window cab. The eight wheeler looks enough like several SP E-classes, so you will get away with running it if you are an SP modeller. MP offered the mogul with its Vanderbilt, which also, is based on a prototype that SP ran with 2-8-0s, 2-6-0s, 4-6-0s and 4-4-0s and switchers. MP was going to issue the eight wheeler with a Vanderbilt, but there was such a cry from the SP modellers and fans. They stated, incorrectly, that SP eight wheelers had box tenders. To be sure, most of them, did, indeed, have box tenders, but some did have Vanderbilts. Harre DeMoro's book on SP steam in the SF Bay Area shows an E-class with a Vanderbilt. Most of the ten wheelers had sausage tenders, but some did have Vanderbilts, as well.
The Eight wheeler and mogul are good runners, once you address the 1970s construction methods. They both suffer from a half wheels live tender. There are several ways to address this. You can scrap the stock tender altogether and substitute a Kato USRA standard tender or a B-mann SPECTRUM USRA standard or switcher tender. Some have stated that the stock MP tender shell will fit the chassis of the SPECTRUM slopeback tender. I have done a test fit, only, but I am aware of others who have fitted the stock shell to the B-mann SPECTRUM slopeback chassis.
Putting an all wheels live tender behind either of these renders a marked improvement in runnability and pulling power.
