Thanks for that info. Didn't know about in-travel adapters. I now know my 2" to 1.25" adapter is a High Hat, which is supposed to give a 16.5mm rise, but my dial calipers show me a full 19mm rise in my own adapter.
So that should fix me up with my Newtonian, which has a 2", low profile helical focuser. I built that scope, and chose that focuser because I wanted a wide(er) field of view for objects such as Andromeda galaxy. I was not disappointed....
But as for my BT-70s, might I find a different (brand? magnification?) reticled eyepiece that will perform better in them? Otherwise, it's to the machine shop with my Sbvony.....