Hi people, thanks for the replies and whew, glad to have someone else out there that I can talk to. I'm not alone then
The guys who are working on the car know Subaru's fairly well and their next suggestion was to pin out the loom between the MAF and the ECU to check for resistance or voltage drop. Joe, essentially, this is what you are saying, yes? No, I don't have a manual and if you could spare the time to scan a couple of pages, my email is roger.stephens (at) me.com - I'd be really grateful, thank you.
I intend to keep this car for as long as a) it will keep going and b) I'm still alive
I've had about 50 cars over my lifetime (50 now) and this has to be the most fun as a daily driver I've ever had. And for no money!!! These cars are SO undervalued.
Again, thanks for your help - I'll let you know how it goes!