$1650 + $1500 labor?!!! That's pretty cheap, especially for an M119!
My M104 top-end rebuild ran about $2300, and the motor was pretty solid at the time!
But even with that low estimate, from a cost-versus-value perspective, it's not a wise investment.
Most of us that are still tooling around with vintage MBs (i.e pre 2000) have probably far exceeded the net worth of our vehicles...it's a labor of love at that point.
That said...lessee...what do I need from an E420 donor car that I can transplant over to my W124?