Mine is on top of dash behind compass. Works great - no more clogged lines. I would bet that the "Mike" you talked to was Mr. Livorsi. He is a customer friendly always taking time to talk to you. Really stands behind product line as well.
I installed mine a couple weeks ago. Hardest part was deciding what to do with pressure line from stock speedo. This month's "Hot Boat" mag has an article on install of Mr. Mike's speedo.