pruyter, The main problem that causes the modification of the transmission tunnel is not the transmission but the clutch release arm on the Mustang II bell housing.
Even the lower portion of the Mutt II release arm is clearly out of the way. Just the upper portion need the clearance.
What modifications you need might be very simple, depending on the bell housing and the release arm you utilize....
A question I have is what if? What if, you used an internal hydraulic release bearing like some of the later Ford's have?
If that could be resolved then for the 2.8 V6, the release arm, hard to find bell housings (mutt II) and tunnel modifications would go away.
DanR
Lets be clear here becuase he is not talking about a T5 or anything mustang II related.
the transmission is a Type 9/N (not to be confused with a T9).
Type 9 and type N transmissions are nearly identical, the difference for the most part is the front shaft and gear ratios. IIRC the Type N was the early 4 cyl model used in the early 80s. If it came from a V6, its probably actually a Type 9.
The Type 9/N has ZERO compatibility to a T5 or the V6 mustang SR4 4-speed to which the bellhousing which is often used for T5 installs in V6 ford engine apps.
The Type 9 is SO much smaller than a T5 that I doubt that the trans tunnel needs modified other than perhaps relocating the shifter hole location.
I have heard at least of installs where the trans tunnel was not modified when used on a ford Zetec engine in an alpine.
The Type 9/N is part of the small ford transmission family (like the pinto/rocket gearbox) and as such uses a different belhousing in ford apps than the larger ford transmissions (like the BW-SR4 and T5 transmissions).
Its not clear to me what the original posters intent is (install the Type-N onto a rootes engined car or to install a ford drivetrain) so not much point in speculating and giving advice that's not relevant.