There are space limitations. The T5 will fit if you use the XF kind of bell-housing. I have no idea about T5 OHC and x-flow transmission differences, but the OHC bellhousing is a totally different kettle of fish to any x-flow.
The OHC has the bellhousing with a starter nested under the intake manifold. It was made that way because the first EA was planned to carry a turbo. And there is no way to place the bell housing or starter in that position on an x-flow...because the back of the cam on the ohv hits the starter.
My friend Rich and I figured out an easy way. Just get the V8 T5 bellhousing and all clutch and gearbox, and run the adaptor listed in the Driveline section. It's fairly simple to build, and it allows you to run V8 gear throughout. The Six and V8 stuff differs.
(Ford Oz ran a simple rule. All six-cylinder stuff after 1982 was downgraded from V8 spec. Auto's, manuals, everything was locally made to reduced cost and weight. The V8 stuff is better, stronger, and easier to get good quality cheap US bits for).