Install Toilet in 1987 Scamp 19 deluxe front bathroom.

[Tcjmiami]

I am installing a shower pan and toilet in my scamp.
The previous owner had built a leaking and rotten shower area that I am replacing with a factory shower pan.
The toilet was installed before with the vent at the back of the holding tank.
That will not work now as the drain will not clear the trailer frame.
It appears that the drain will clear the frame with the vent toward the front or back of the trailer.
It looks like you might get more room with the vent toward the back.but there might be a clearance issue.
Does anyone know which way it should be installed?

[Tcjmiami]

FYI

I installed the toilet with the vent to the rear and had to place a 1" spacer under the toilet to butt it up completely to the port side of the shower pan which is touching the outside of the trailer.
The holding tank drain pipe is touching the outside of the frame with this combination which was the best of the choices I had available.