If you nay be interested here's a u-tube version. I think he sounds better in person.
The tables are 30" high to match all of the other tables we have.
To support the machine from below: (1st photo below)
First measure the height of the machine sewing deck to the table top it normally sits on. (deck height)
Next on each side of the new table 1. allow 1/2" for MDF table top and then measure down the side of the table (deck height). Draw a line there. Next measure down another 3/4" more to allow for the board that will lie flat from side