I figured out the best way for anyone who needs to do something similar. using 'slice' is out of the question, the remapping and interpolating just takes WAY too much computing time.
Instead, it was very quick and efficient to just recreate ONLY the slices I wanted to display via for loops, then use the 'surf' or 'scatter3' to display these. Even though they were 2D slices, they were still represented by T=f(x,y,z) coordinates in 3D space, so that's how I went about it and it did exactly what I needed it to.