If you are putting in an L block, then you need a L gearbox. Short ones come from 510. Z-engine gearbox will bolt up but have a 22 degree different tilt.

The clutch is interesting on L-series.
* use the L20B clutch, as there are three sizes and it depends on the flywheel. L20B has the largest size
* the release bearing Sleeve length needed depends on the clutch cover (pressure plate)

Even though I'm using a z head? I thought I'd have to swap the engine brackets around to straighten the block as I'm using the z head thus having to use a z gearbox or am I wrong :/

I think you are right. So the L engine brackets will be the wrong type?

Short Z gearbox comes from some 720 (other 720 have mid-length or long gearbox). You want a box same length as your gearbox now, which is probably a stumpy

I think all I have to do is swap them around. That's what they used to do for putting in a z18 in a s1 L series 910 here

Use a Z bellhousing with whatever gearbox you decide on. Stumpy box in Oz from 1600/510, Stanza or R30 Skyline. If your not in a hurry for the gearbox I have one in storage with a clutch and flywheel. i can bring it back to Adelaide next time I go bush.

U will have to let me know. See if I've got the $. Always spending my money on cars :p

MADDAT in the Adelaide hills are the Datto Experts.
They can make you engine mounts to suit what ever you require.

And you would be supporting a local Adelaide business.

Cheers
Geoff