So here is an update, the 3dfx installer for mercs doesnt work here at all, even the old cd i had as "other means", so it must be hardware related issue due to the 2600x i am using.
But the 3d positional and 3d enhanced version works as mech2.org 1.1 patch for it which has the mechprep i spoke earlier that changes the game resolution, which makes me wonder if its possible to use mechprep alongside dxwnd to increase the game res to full hd, or have dxwnd use dgvoodoo's own ddraw to crank the res to full hd.
Also Audio works because i am dumb and i forgot to set dxwnd to audio files.
The attachment Mech2edfx aspectratiocrt on msaa8x lanczos3.png is no longer available
Here is Mech 2 3dfx in its all glory and "wireframe" mode, all is left now is the hud transparency issues, but is working flawlessly.
Though a .MAP edit to add modern KBM controls would be necessary.