Have you considered something like a GTX 63 or 67 mm machined into stock style housings? It's been done before and will give a much better result. There have been a few guys that have done that on here.
Get a decent sump made. Forget that trust 44 gallon drum junk.
I have a 9.5 litre sump and it's not the lowest point up the front of the car. Maybe contact rips in NZ and get him to make you one.