>Whole EJ20 turbo front end, with WRX brakes etc, I believe I need to source L series control arms to get some negative camber and ream the holes for Wrx ball joints and use early WRX front axles for correct length.
That's pretty much what I've heard done. I borrowed a reamer from another member here but left the mix-and-matching to a Subaru mechanic as he had access to all the odd bits. One trick I did learn was that 1993-94 Liberty wagons used a rear tapered spring that leaves plenty of clearance, while other models don't. I've not heard of the latter being a problem for other 5-stud conversions, but putting the info out there.
>Then join front part of Wrx drive shaft with back of L series shaft to get right length to join to a R160 or similar diff. Change the cups in the diff for MY rear axles and get Xt6 or Cr0ss... Hubs for better brakes and better wheels. Is this your plan?
I have a MPFI 5 speed, so my output count is different from most. If you're going a WRX engine, I'd suggest either grabbing that AWD box that was/is for sale (in the FS section!) so the power is more evenly spread. I'm only going SOHC EJ20 NA, so I didn't see a need for it. Bennie will tell you to go the EA-into-EJ box option so you don't need an adaptor plate
My rear was much simpler. Just Forester backing plates redrilled from 4 holes to 3 (2 of the 3 original holes mate, the 3rd one needs to be drilled in the backing plate, fit the XT6 hub as per usual MY process (tighten it to infinity), bolt up disc, bolt up caliper. Route the handbrake up the suspension arm into the cab. The ********* kit is the same except it adds an adaptor plate to convert the 4 holes on the Forester/Impreza/etc vehicle to suit the 3 holes on the MY.
1989 Brumby - Shiny new red paint, stroked EJ20 phase 2 SOHC with Darton sleeves bored to EJ22, Wiseco high-compression pistons, Delta 2000 grind cams , EJ/XT6 5 stud with WRX 4/2 pots, 5-speed, 86 GTS seats and so much more.
Contact me for reproduction XT6 hubs...and EA82 rear discs.