The only advice I would pass along is that if you are going to use tubular lower arms (eliminating the strut rods) then you will want to go with as stout a crossmember as you can find. The strut rods were an integral part of the original MII suspension and transfered some of the suspension forces to the frame. Eliminating the strut rods apparently puts additional "twisting" stress onto the crossmember itself. Hotrodders.com has some horror stories about MII crossmembers that cracked under the increased strain.
I had originally planned to go with the full tubular lower a-arms until I held them in my hands and saw how they were designed to be mounted to the crossmember - 3" piece of tubing welded to the back of the crossmember with a gusset. To me it didn't look like a good idea, but hopefully the crossmember manufacturers did their homework before they redesigned the lower arm/crossmember like that.
