Ready made trains

You might try being a bit more specific as to exactly what you're swapping with what.

It would be swapping out the rmt beef b uint shell with a traditional Taylor made trucks shell

Hmmm Never Tried that.  If the B unit chassis is the same as the Beep's, it should work.  If the chassis frames are different...hmmm applies.

Even Walt Matuch, Founder of RMT, may not know the answer.

Ed Boyle

It has the wire tether 

In reply to Ed Boyle...

Walt Matuch/RMT does know the answer as I/Walter made the design changes.

RMT BEEF A-B unit bodyshells were actually a K-line E-8A bodyshell cut in half at factory with new end cap added to create an RMT BEEP A and B unit that would fit exactly on an RMT BEEP chassis. TTC/Toy Truck Collector by Taylor Made Trucks BEEP bodyshell will also fit the BEEF B unit chassis. 

NOTE: The location of the 2 dimples per side on chassis frame above fuel tank allow for directional mounting of BEEP bodyshell as long hood forward or short hood forward position. BEEPs from factory came as long hood forward as 'standard'.

The last production RMT by ARISTO had both BEEPs and BEEFs (A and B) with a tether connector on each BEEP or BEEF B unit  and 1 on each A unit rear end to allow a continuous center rail power pickup on 2 or more so-equipped diesels when traversing switch tracks. These 'connectors' were male and female opposite ends to allow MU diesel capability such as A+BEEP+B+A or even BEEP+B+ BEEP. The circuit boards were upgraded on this production to allow a more scale top speed of about 42mph.

The BEEF B unit did use same chassis as BEEP but had notches cut in each corner to allow B unit bodyshell to fit properly. Otherwise no modifications were made to chassis so a BEEP bodyshell could be swapped onto a B unit chassis.

However, the some circuitry for the B unit was attached by double-side tape to inner roof of B unit to allow 'see-through' portholes on B unit bodyshell. This would need revised placement when using a BEEP bodyshell as interior  dimensions of BEEP and B unit bodyshells are different.

Now you know and can share with the entire world.'Little-O Gauge' Ed Boyle shown here.

Walter/RMT shown in cab of BEEP.

Walter/RMT

Thanks rmt and a Walter 

Walter how do you go about removeing the tether from the shell