powerglide to mopar small block adapter questions

I am running a stock A518 trans at the moment but it wont last long as I keep burning the oil. It is giving me mid 600s HP at the wheels but because the stock A518 cant handle the power I am running in the high 10s down the quarter mile. New trans will be a massive improvement I hope. We don't need to run a cage in our cars here in Australia until we go faster than 10-5 quarter so I am not running a cage yet.
Yesterday I found a guy selling a JW bellhousing and an adapter boss kit so I can run a GM converter and flexplate and starter.
I thing it will be easiest to just buy this so if I want to change stalls etc down the track I wont need to have a custom converter made each time.
Thanks for the help everyone;)