John Doe wrote:
1] The 160m whip assy that I originally planned to use is CENTER-LOADED
which I think is better than a base loaded whip?

Yep, and a center-loaded 40 ft. long wire is better than
a center-loaded assy shorter than 40 ft. on 160m. There
is no perfect substitute for length and height on 160m.

2] If I decide to go with a 30 or 40 foot length of bare wire up the
tree, How long should the TOPHAT wires be?

As long as you can make them and as many as you can
manage. Best to check the resonant frequency during
the installation process but you are not likely to
make the top hat too big on 160m with a 1/12 wavelength
vertical wire. Resonating the system using only a large
top hat would be ideal. Of course, you will be dealing
with a low feedpoint resistance, too low to be matched
without a ~1:4 unun or equivalent.
--
73, Cecil http://www.w5dxp.com