removed the bolster from the plastic BLI underframe and replaced it with a block of styrene .160" high drilled and reamed to fit over the cast post on the BLI floor. Then I drilled and tapped the post for a 2-56 screw.

    I just looked at Andy's pictures.  Seems another route might be to build a dam on the coupler end and fill the hole with resin,  frame needs to be level.  Save a lot of filing.  Then drill and tap.  Thoughts???

-- 
Jon Miller
For me time stopped in 1941
Digitrax  Chief/Zephyr systems, JMRI User
NMRA Life member #2623
Member SFRH&MS