Without pics it's hard to say. Personally, if I were in your shoes I'd be looking into the correct replacement trans. In my past experience with trying to adapt what I have on hand, it cost me time and money that could have been spent to buy the right stuff.

Don't get me wrong. I'm not the guy over your shoulder sayin' 'I told ya so'. Some adaptations work, some not. It's all trial and error. And being on a budget forces one to put it to the test. I was once a grasshopper.