Yes, that's the bit of machinery I was referring to. The tubes are a little short but as you pointed out it's going to depend on how much room you've got to play with! I assume this is a 947' long ship you're playing with?
The Engineering set was also used in The Enemy Within
although the tubes are viewed at a slant. But that episode did give us the ceiling
above those two big power units which were always being moved around.
Court Martial has a couple of blurry shots while Finnery and Kirk beat the tar out of each other, although this is a nice one
The tube machinery did not change when the Engineering set was re-jigged after the 1st season, so these
from Journey To Babel
are quite useful, being viewed as almost straight on.
You're right of course that the tubes were built as a forced perspective; as such, they change their apparant length depending on where the camera was at the time. A common setup was this:
...where you can see far more tubes than you should if it was "real". Fortunately the fandom has explained this away in numerous ways, so there's no problem using a "full length" tube set! However, it does illustrate the limitations of a FP set quite well.
As with all FP sets there's an optimum place of viewing - while I can't say for sure, I would imagine it's about 24' away from the centre of the grill, from about 6' off the ground (in other words the back wall of the set at head height).
Of course, the only way to really test this theory is to build it and have a look!