I am finally acquiring a Z6ll and I initially want to continue to use my F mount Tamron 100-400mm. I know from previous queries that this Tamron works with the FTZ adapter. Since I am moving from an APSC DSLR, I am used to an equivalent range of 600mm on the long end. Therefore, in using the Tamron on the Z6ll I am considering at least a 1.4 teleconverter to maintain some of the reach I am used to. Seems like a lot of connections to maintain rigidity. Has anyone ever had problems with stacking ftz to teleconverter to lens? If so how have you solved the problem.