russ d
+1y
I guess I dont understand what you are asking.
If you are thinking that you can z your frame 3.5 inches and lay rocker, you are not thinking clearly, or dont really know what a frame z is.
A Z is where you cut the framerails right behind the front suspension and move it up a little (or a lot). You usually do this because the front crossmember hangs a little lower than the framerails, which gives you a "ghetto lean" when laid out, where the front is higher than the back like the old ghetto cadillacs in the 70's.
A Z can be done WITH a bodydrop, for example I gave my frame a 1/2 inch Z when I did my stock floor body drop, and it lays out super hard.
But if you move the corssmember up 3.5 inches, it will just be 2.5 inches higher than your framerails. Mazdas only need about an inch to make everything level. You wont lay rocker, still, until you lower the body with respect to the frame. Your comment that "nothing else is in the way" is confusing, because you cant cut the lower part of the frame off, EVERYTHING would hit the ground, tranny, crossmembers etc. You still will need to body drop the cab.
If you are just talking about doing a regular bodydrop and z'ing the whole front clip instead of cutting off the whole core support, you can save a LOT of time by just cutting off the "ears" that hold the core support and dropping them the amount of your bd, then notching the core support crossmember for the lower radiator hose. Took me about an hour to do.
A 3 1/2" frame z would mean you would need to raise the tranny to match, and that would hit the tunnel.
Clarify step by step what you are doing, I'll help out anyway I can.