904 Conversion to 727 in early a-body?

The mount is the smaller of the problems. When I put the 727 in my 65' Valiant I drag race I had the put a bigger tunnel in the car because the stock tunnel was not big enough. This is with a 75' 727, the mount on that trans went right in the stock crossmember and was able to use the stock a-body engine stands. I do not remember what the mount position is on a cable shift trans, it's been awhile since I looked at one. I just know the distance fron the block to the mount is the same on later trannys, or at least the ones I've seen. I would just beef up your 904. I was going to run a 904 but desided on the 727 in case I wanted to upgrade to a big block later.