Transmission rebuild 904
Check the year of the 273 & trans. Early 904 converters had a smaller snout than 340 cranks and you couldn't just swap converters because the splines were different in the transmission.
"True" triple valve springs are too much for a conventional flat tappet cam, unless they are doubles with a damper.
Valves???
Cheech14 posted: "Cope has ceased to do trans builds and is just selling parts now."