EFI-DIY and someone else have been tinkering with those, someone has one running in an older truck (on this forum) but I can't seem to get the search function to work for me today
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EFI-DIY's main post (that I can find now) is titled 4200 Turbo Project.
There was a thread on a group buy for cam blanks and a billet turbo exhaust manifold (might be in the 4200 Turbo Project thread, haven't gone back and re-read).
I have kept up best I can as I think it's neat, but I don't currently have one or a project I'm likly to stick one in, sooo I haven't gathered any parts (yet). If you think you might be building one up though, you might consider getting whatever you can lay your hands on, as I don't expect the availability to get any better in the future
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