Go to the link below.
MSHRED is selling a high quality converter that looks to be what you are looking for.

Re: 8" A1 race converter for 904

https://board.moparts.org/ubbthreads/show...rue#Post8102908

Quote:

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A1 8" race converter for 904 for sale!
Went to 5500 rpm off the brake behind my small block. Used for one season only, regular fluid changes to keep everything clean, excellent condition. Only selling because I am going to a nitrous converter
$800

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