I installed a liquid filled fuel pressure gauge on the lid of my plastic filter housing lid. I know it was a risk of cracking it but 2 weeks and no leaks at all. I Got a 1/4 pipe tread (male)fiting and screwed it into the hole centered in the hex head lid. It is a prefect fit. I know it is palstic but it is thick at the hex center. I drilled a tiny hole (. 050) at the bottom of the hex center hole to tap the fuel pressure. If you use a male 1/4 to female 1/8 adapter you can thread an 1/8 gauge or hose to the lid. I used a gauge (0-15psi) from northern equipment (pn 53652). It is small, about 1. 5 diameter so you can still get in to remove the lid if you do not want to take the gauge out of the adapter. As a bonus just loosen the gauge to bleed air out of the filter after a filter change(air rises to the top of the canister). A cheap hose can be bouht to remote the gauge for trouble shooting (pn 50048, one wire 48'' 1/4 hose). I figure if the thing ever starts to leak I can find some way to plug a 0. 050 hole if I am in a bind. My pump is at 13 psi at idle, so i guess it is okay? The number for northern tool and equipment is 1-800-222-5381