McChilken,
You just drill the backplate in the center and tap for the 6-32 fitting they supply. The 160 FX has a entrance for the fitting on the top left backplate screw that you can drill and replace the screw, not sure about the 75AX. Just remove the backplate and drill it, make sure you file off any protrusion on the backside. This is about a 5 minute job.
The other thing is use the supplied tubing and don't replace with fuel tubing, that will blow off during the pressure cycle, (not good)
I'll get some pics of my installation.

If your worried about warranty just buy a seperate backplate to install if you have to send it in.

A couple of key points, make sure the vent hole is pointing down and the pump is level with the carb inlet. Don't even mess with the adjustment on the pump as it does'nt do much. It's all in the LS needle setting to get these to run correctly, and to smooth out the midrange.

Don't forget no muffler pressure, just route the line to exit the cowl, with the pump you need a tank vent.

These pics show with a fueling valve so don't get confused on the plumbing. If you have a fueling valve it has to go in after the valve. The second line you see going by the pump is the vent going below to exit the cowl.

Can I ask what your tuning instructions are? There's only one way to tune these or you will be pulling your hair out.


This is the one you want,

http://www3.towerhobbies.com/cgi-bin...?&I=LXDG59&P=0