Sure, I'd love to.....been meaning to reflect on the install.
I started by gathering pics and details of existing 912 installs. There's not much out there, but as far as engine installation, the Lockwood 912 Super Drifter has similar, if not exactly the same dimensions as my Austflight Drifter. The wings, flaps, main tube, etc may be different, but that is somewhat irrelevant.
My biggest concern was CG changes. The Lockwood bird fixes this by lengthening the fuse tube forward of the CG. Not an option for me of course. Instead, I chose to focus on doing the lightest install possible, and moving weight from the tail to the nose.
My actual main motor mount beam is a Lockwood part (they insisted it wouldn't work on an Austflight, it did.). I removed the old mount, positioned the main beam and drilled and bushed the existing down tubes. I also chopped off the main wing root tube aft of the fitting. At this point I was committed. The most difficult part was designing a lower bracket that would adapt to the existing one. I used a stainless steel doubler spaced with aluminum. This part is impossible to explain, I'll have to post pictures.
I then fabricated the alum bars that the motor mounts go in. You can purchase these from Lockwood if you don't want to build em, but it was easy.
I was unimpressed with the component installs on a lot of the 912 drifters I've seen. Some have the oil tank mounted to high according to Rotax spec. Some have the radiator under the engine, behind the fuel tank. I could certainly be wrong, but that seems like it would get lots of vibration, require complex and long coolant lines and a larger radiator due to reduced airflow. So, I rethought the mounting of my components with CG in mind, and it worked out awesome.
My radiator is a lightweight one off a shifter cart ( small race car) and is mounted to the aft main wing root bracket in a clever system using large rubber bushings. It's secure, far enough forward, and doesn't get a lot of vibration. The radiator itself is much smaller than others I've seen on the drifter, but is still way to big, given the airflow in receives. Coolant capacity is approx 1 gallon, which is almost twice rotax recommendation. I use NPG coolant and still only get 170 degree CHT on an 80 degree flight. I have to block off some radiator with duct tape if OAT is below 75. I'm planning to replace the radiator with one of the same dimensions, except thinner, in order to save weight and keep CHT where it should be.
I mounted the oil cooler to the main beam just above the fuel tank, as far forward as reasonable. This works well and places it within rotax spec as far as height in relation to the engine, something few 912 Drifters do. This is important.
The last hurdle was fitting the air cleaners where they wouldn't interfere with my flaps. I had to shorten the flap rods, move the brackets outboard, etc. I also had to abandon my original exhaust plan, as the exhaust tubes were to close to the flaps. This install would have been much easier without flaps, and the drifter doesn't need em. If I could have used the better exhaust, it also would have been a bit lighter.
I went with a 60" 4 blade prop, but now wish I had a 62-64". There's more clearance than with the 582.
I've now got almost 40 hours on the aircraft since the conversion. It's been great. The 20-25 lbs it gained in the conversion is not noticeable. My drifter is the strut braced flapped version, so it never had sporty handling. CG is within limits for up to a 190 lb passenger. I removed the trim tabs on the tail, moved the strobe up the the top of the radiator, and lightened the tail wheel.
Cruise flight with no passenger is about 4500-4600 rpm. Climb is way more impressive, it's quieter, more reliable, and burns less fuel. I'd estimate my fuel burn to be 2.8 gallons / hr average. Maybe a bit less. It turned out to be a fantastic aerial photo platform, which is what I wanted. The added benefit of being able to take friends and family up without so much worry is great (density altitude here in the summer averages 8,000'). I also find myself going farther and longer with the 912. i was planning to take it to Oshkosh this year (1000 NM one way) but weather got nasty.
I've always LOVED 2 stroke engines, especially the 503. I've owned and flown many ultralights, and still believe that the 2 stroke isn't necessarily less reliable just because it's a 2 stroke. That said, this 912 conversion was everything I thought it would be.