Having trouble getting shifter to select low gear

Not really, looks like you have a transmission that doesn't have the cast in ears for the floor shift bracket to bolt to and its been modified to bolt to the transmission pan instead. That should work though but its only using one bolt and probably letting it move from adjustment. I believe if you extend the homade mounting bracket to use two bolts so it can't move and then readjust your linkage it will work.

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thank you for your help so you think its not the original transmission?