First find out if in the biggest trucks offered with a 292 did they use a transmission with an SAE (round) clutch housing. If so those are the parts you want. Perhaps a model with an Allison automatic or a 5000 series Spicer?
I removed a Spicer with SAE housing from a 60's C80 that previously had a 409. What other engines share clutch housings with the 292, and can you find SAE stuff for one of those.

The smallest Roadranger transmissions only came with SAE#2 housings, ideally you can find factory GM stuff also SAE#2.

If no luck there look at the aftermarket solutions

•1951 GMC 250 in the Project Journals
•1948 Chevrolet 6400 - Detroit Diesel 4-53T - Roadranger 10 speed overdrive - 4 wheel disc brakes
•1952 Chevrolet 3800 pickup
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