Hey all. I have read and re-read several threads on how to: fuel pump upgrade and I have all the parts ready and understand exactly what and how. The only question I have is exactly which holes need to be ported so the siphon still works properly to pull from the other side of the tank. There are plenty of pictures but I haven't found anything clearly identifying which one needs to be drilled out. A pic with an arrow would be most helpful. Sorry if this has been covered already. Search function still leaves a little to be desired in here.

Thanks in advance!

 

this I can assist you with as I've already done mine. Obviously everything you do is at your own risk. On the return line within the pump housing you will find this (see first pic) pushed down inside its own separate housing, you will also need to un clip the grey end on the black hose from the main pump housing. Carefully pull it out, it is pushed into a plastic clip which you can't see until it's out. Next thing is to pull the top part off (part with the mini black hose attached), it is held on by two clips located on the sides (can be seen in first pic). Once the top part is off, flip it over (see second pic) and you will find a miniature filter that clogs very easily...most recommend to remove this if you are running an inline filter. To get it out I used a heavy threaded screw, screwed it in a little way and then pulled it out (see pic three). Now you are done with the top part. Next grab the bottom part and look inside from the top down (see pic four), this is the orifice everyone talks about that needs to be drilled. Drill it out to the size you want (you can see the difference in picture five). Once your done put the top part back on, push the whole piece back into the pump housing, reconnect the grey clip and you are done with changing the orifice size.