That cover plate is my existing setup. Only a small hump in the front. It’s the same plate for the original hydromatic supposedly. There is one other GM option for an original four speed tranny

https://www.autometaldirect.com/pro...YRQeBaelUL3fI9cLGAnJAjitaKwaAj9pEALw_wcB

If not this 4 speed plate, fabrication will be required as the back of the plate comes up against the seat munting rib.

I included a pic of my existing plate. It’s held down with 9 screws.
Attachments
IMG_2925.jpeg (156.89 KB, 104 downloads)
Transmission hump/cover plate


1958 Chevy Apache - "Stella"
"Start to finish w/upgrades"

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