anyone know where there is a t5 gearbox right up looking to rebuild a t5 gearbox soon as a project had a quick surf n couldnt see watched https://www.youtube.com/watch?v=n9FVZ3YQ4CU but they didnt show how to do the reverse gears.

Look under AutoRestomod for T5 teardown and assembly on youtube. Also, read through the repair manuals and get a pdf of the Tremec document (which is easy to find on the net).

Have you got a shop press and bearing clamps to remove the gears and bearings?

The countershaft and reverse gear idler are easy to get out once the mainshaft is removed.

the link given was there video il get the pdf n read it yeah iv got a press i can get a bearing clamp i suppose

The link you posted was the main one I used. Three things to remember when doing the rebuild:

1. Use ATR when pressing parts on or off. I jammed the 5th gear onto the mainshaft and had to cut it off using a grinder. Should have lubed it with ATR first.

2. Mark the 1-2, 3-4 and reverse synchroniser sleeves and hubs before you pull them apart

3. Make sure the retainer springs hook into the same key and run clockwise on both sides of the synchronisers