Just thought I would start this tread for anyone who is interested in fitting a 6 speed gearbox into their Series 80 1HZ. I started the project a few months ago and the big issue was selecting the right gearbox. Looked at everything from the land Rover Discovery and all the late model 6 speeds and decided on the MT82 out of the 2013 Ford Ranger. The main reason was the easy by which it could be realigned from a Passenger side drive shaft alignment to a driver side to suit the 80 series Diff input. For the moment I will park this thread, gather all my photos and story details and progressively update it over the next few days. In summary, after over a Million kms I decided to give the 80 series motor a refresh and while I was at it, a gearbox upgrade which has been well worth the conversion and did 75% from my home garage. Apart from buying the gearbox the whole conversion cost about $700. Update 1: Just as an opener and I apologises if this offends anyone who fits this category, but as with all forums there are always people who provide opinions ! based on very little or no first had experience yet claiming what they say is with Gospel accuracy. If this is you please go play in another topic. However if you have any serious doubts or thoughts about something then I am more than happy to explain my finding and experience. Yes the car has only been on the road a few months and the test of time is yet to reveal its issues. Secondly, this is purely an "experiment" and aimed at solving the age old question of giving the 80' series longer legs for high way running and much better ratios (2-3 and 3-4) between gears on hills that suit the engine. Selecting the gearbox: As I mentioned the MT82 is in a lot of vehicle and is coupled behind lots of different motors. The Mitsubishi BT50 and Ford Ranger both have the 5 cyl turbo motor rated at about 470 Nm of torque and compared to the 1hz's of any version, is way over rated for the job. The three main questions I was interested to solve (apart from the strength) was the rotation of the output shafts, realigning the output shafts from passenger side to driver side (as per old 80 box) an matching the gear rations to match the 1HZHDT torque band between gear changes better than the old box. This was done in two ways. Gear box ratio comparison Gear 80 series MT82 1st.......4.529........5.441 2nd......2.464.......2.839 3rd.......1.49..........1.721 4th .......1...............1.223 5th........0.881.......1 6th........N/A ........0.794 Diff ........4.11 .........4.11 Upgraded diff ratio to the 80 series EURO diff ratio 3.879 (Jap, SA, USA and Aus was 4.11) The next thing to do was to get a box and old 80 series bell housing and start measuring up to see how to match the two together and what work needed to be done. The major differences I found were these. Clutch hydraulics uses a concentric cylinder Input spline was different Box was 150mm longer Output to rear wheels was direct alignment from gearbox input and not from T/F case. G/Box bell housing was incorporated with the G/box. No separate Bell housing. There were lots of other minor things that 95% of us could easily work out. The first and most important thing was working out how to couple the MT82 to the motor. I thrashed through lots of options and decided to machine both the 80 series and the G/box housings down, tig welding a 15mm thick adaptor to couple the two together. This had to be very accurate so as to suit the input shaft length and support bearing in the crank shaft. I have all these measurement is anyone is interested. A huge issue was I couldn't find anyone engineering workshop who would take on the job of machining the MT82 bell housing with out stripping the G/box apart so with a lot of creativity and lateral thinking I did it my self. Will post a vid to show you how simple it really was. The second part of the adaptor issue is the clutch and support bearing in the crank shaft. I managed to find an "Off the shelf" heavy duty organic clutch that had the exact internal spline of the MT82 and its O/D fitted the 80 series pressure plate perfectly. A bit of good luck. The other thing I found was the O/D of the MT82 input shaft support bearing was exactly the same as the I/D of the STD bearing used by Toyota. This was a pure fluke and a good omen.. That's it for the moment and will post some photos and vids of the bell housing machining method I used. Remember I did it all from my home garage so is very unorthodox.