Are gaskets required above and bellow the Alloytec manifold insulators (manifold spacers) for the install?

Given the gasket like properties that the insulator material has, no additional gaskets are required. However silicone sealant is required to be used, which is included in the kit at no extra cost. For further details about this, please check out the fitting instructions in the link below:

http://www.maceengineering.com.au/WebRoot/ecshared01/Shops/mace/4E1D/8C2F/7D5F/672B/E9DD/C0A8/D240/2EA6/ALLOYTEC_MI_INSTALLATION_.pdf