mark
+1y
the notch height will depend on wheel/tire combo you are going to run bro
if you plan to lay it out with the stock mazda tires, 215-70-14's, to lay frame on the tires my axle sat about an inch or two above the top of the frame....so it isnt much really
you can actually get away with having the tank behind the axle and not having to cut the bed floor....but the tank will come crazy close to the ground and you might as well not have moved it hahaha, but me i set the top of my tank to bean inch above the frame, so i had to cut my bed