You may need a different gearbox cradle as most sierra were a 5 speed apart from the 1.3. Use sierra mounts and id say you were away with everything else. Ex manifold may be different but use the sierra stuff and its a straight fit id say. very easy swap and could be done in a few hours. Why use the 4 speed though. if you have a sierra that the engine has expired but eveything else is there then just use the bare block and head and everything else from sierra