That looks like a standard, clamped barbed fitting.
There is no way in Hell that barbed fitting is going to survive more than a few cold-starts with high oil pressure especially with no clamps.
"Jake the Mechanic should know this (or he simply doesn't know what a full-flowed aircooled engine is all about or he's totally BS-ing you).
Seriously, you need a better "mechanic". This guy's costing you a lot of money.
@PaulEllis lives in the Phoenix area and I would trust him. Find him on here and get in contact. He knows what he's doing on these cars and then some.