You are walking a fine line, my friend. I would make sure that you are very closely watched my your kidney dr while you use. As I am sure you are well aware, kidney issues can go totally unnoticed for a long time. Test is really your safest option, IMO. If you are healthy, you should be able to gain a lot on 400mg test. I've worked with guys that have changed their entire look with less. Average guys, that have always been healthy, should focus on using the least amount of gear to get a good effect, relying on diet and training to gain the most amount of weight possible. For you, its even more important to get the most you can, out of the least amount of gear. A small mistake in over dosing a compound could cause major problems for you. Anything that makes you hold more water puts more strain on the kidneys, espeically if your blood pressure goes up.
Adex is probably a good idea with your test, to control estrogen and keep water lower, therefore keeping BP in check.