My sister and I repurposed her huge computer desk to fit her machine last weekend. We removed the hutch and cut for the machine. Sanded and rounded the edges of the cut and she painted it. We took one of the shelves and attached to the underside of the desk with long bolts, large washers, and nuts. We were able to get it perfectly level and at the correct height using the nuts as adjustments. (saw this on this board in another post, can't find it now.) It works great and was easy to do. Not sure how it would be on a really heavy machine. This is a Kenmore 385.1960180. A solid machine but not an anchor. I know I wouldn't put my grandmothers Nelco in there, that thing weighs 38 pounds and was advertised as portable.
This was easy to do. Even with painting the top, it was complete in a day, really just a few hours. There is some really quick drying spray paint now.