I did not realize that the N scale Spectrum HHP does not come with knuckle couplers any suggestions on switching them?
Try this link:
http://www.trainboard.com/grapevine/showthread.php?t=57499
I did a how to pictorial on one of the other forums. I used the MTL "T" shank coupler and it worked very well. There was a bit less cutting involved then with Steve's install job, but Steve's instructions work very well.
Could you please post the link to your pictorial so I can compare. I am a novice modeler and need to use the simpilest approach.