On my 79' Scarab I am changing my exhaust from the old log style to center rise with captains call. Do I need to change thermostat housings, I have twins? And how do I mount the fuel filter now, it use to mount on the end of the old log manifold?

are you planning-hoping to gain hp? if so save money for a real exhaust. if you are replacing them cause they are shot and you are happy with the boat as is, there is an L-shaped bracket bolts to front of motor for fuel filter. t-stat housings could be reused, but they are getting pretty rusted up...