Is there a simple way of doing this?
I just made a test track, using a metre of track and leaving half a metre of space to attach various points (to check slow running over the crossings). Unfortunately I inadvertently used code 100 track, and the points I want to check are code 75. I also imagine there are plenty of people who want to use up old stocks of code 100 in fiddle yards.
I mainly model N gauge, the OO is just for fun. There is no problem joining together both codes of Peco N gauge track as the code 55 just has the extra bit buried in the sleeper moulding, but the OO track has a different rail height.