In my case, using a 235 mounted in it's stock position, using a TH350, in a 1955 1st Chev PU, there was no way to leave the crossmember.
I would in no way do this conversion on my own truck but with customers I have to do what they want(I warned him first).
The main thing I do not like about cutting out or weakening the crossmember in any way is that the front cab mounts attach on brackets on the outside of the frame in this same area.
If you modify the crossmember the cab mounts will be allowed to continually flex the frame on every bump.
This is already a weak area of these frames. I have needed to weld up cracks in many of these frames in this same area.
