u should be able to do it over a wkend, just make sure u got an alternative method of getting to work on monday in case it dosen't go to plan! as said, get a workshop manual, round up a couple of mates who aren't useless and give it a go.
double, even triple check all hoses, pipes, wires etc are disconnected before u yank out the motor, nothings worse than someone snapping bits when all the shops that sell replacement parts are closed:banstick:
its possible to install the lot in one piece if u can get it tilted enough that the back of the box clears the firewall/trans tunnel but there's more chance of denting the firewall/radiator support if ur not careful, if u go about it this way either drain the trans or stick a spare yoke onto the output shaft or else u will make a hell of a mess!
i normally install the motor and box separately cos every time i try and bolt them in as one the back of the trans hits the ground and wont go any further before the front of the motor has cleared the radiator support (this happened swapping V8's in a VH, with the 6 being shorter u probably won't have this problem) if u do it this way make sure the convertor is located properly on the front of the trans. if converter hits flexplate before bellhousing hits block its not right. dont try and pull the box up to the motor by tightening the bellhousing bolts cos u will break the trans oil pump drive. the manual will tell u how to get the covertor on properly. good luck with it
