89' Econoline with mystery fuel problem

We have an 89’ Ford Econoline 150 van. The van is so dear to me is because it has a manual transmission. Right now it has a fuel problem. The last time it started it ran really rough so I turned around, headed home, the engine died, but there was enough momentum to coast into our barn driveway. After AAA towed it my mechanic replaced both fuel pumps the PVC valve, and who knows what else. In the process of replacing the fuel pump in the gas tank the rusted straps broke, and he had to replace those as well. Now it will start but one has to spray engine cleaner into the intake first. When the “key” is turned to the engine on position (but not started) the fuel pump stays on instead of cutting off after a second.
The next thing to replace is the ECM (engine control module) but it is nowhere to be found. We haven’t torn out the dashboard yet. It’s been sitting at the mechanics since June.
My wife Patrice wants to junk this van, but where else am I going to find a van with a manual transmission? Will it ever be a dependable vehicle again? What to do?

I converted the inside of the van to carry our miniature horses by fiberglassing the floor, and put in little dividers so the little horses won’t kick each other in transit.

Earlier this year the ignition switch kept sticking while I was starting the van so the gear on the starter motor would get stripped. It was a vehicle that required a new starter motor every time it was started. My mechanic solved the problem by installing a starter switch under the dash. I put a screwdriver in the slot, push down and it starts.