Mth 4-4-0 30-1135 upgrade

I typically move the tach reader to a different position and roll my own holder.    The reader bracket is pretty bulky, so losing that is key in some cases.

I actually upgraded one of the MTH 4-4-0 locomotives many years ago, not sure I remember if I had any issue with the tach reader, but it runs fine, so I must have licked any issues.

i admire the design on this the motor just fits in the firebox and the flywheel is tapered to just clear the boiler casting.

on a happy note I found a tiny weight attached to the chassis just under the motor. I popped it out and the stock tach sensor will now clear fine under the motor. Now to squeeze another 5 lb of wiring in a 2 lb bag!

Here’s a pic for those interested.
i just noticed little notches in the shell to clear the motor mount! No extra space on this one. Motor wires are a tight fit I may have to play a little with routing.

What if you reverse the tac reader? 

I use the tach reader with no spacer and then use Styrene strips to space it from the flywheel and glue it to the motor.  That gives you the lowest profile possible.  You can also move it slightly around the diameter of the motor, offset to one side it appears there'd be more room.  Consider sliding it around to one of the indicated positions.

Normally they are on the bottom of motor as you show.  Are you saying the motor does not fit back on the chassis?  Because that is where it would be.  The shell should fit.  YOU can't put on top of motor, that is usually where it would contact shell and potentially short to chassis ground damaging PS board.  G

No it fits on the bottom now. There was a little lead weight glued in the chassis under the motor. I pried that out and now had room for the tach.