I think the technique is to listen to the tune while reading a version and catch the differences.
Having heard the new version you provided, Stewie, I think I'm hearing "All these goons in this great land" quite clearly now, and I'm happier with "lovely flat" even though it doesn't sound very American - I suppose "beautiful apartment" wouldn't scan so well.
"Till your house fills back of van" still sounds wrong, unfortunately. I'm struggling between two nonsensical translations - "till your house key's back upstairs" and "till your house heels lack a bear". I think you're smack on with the rest of your alterations, though.
Cheers
Ray