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Trasmission line questions and more for a new QTH

Well I finally have a place to operate, and best of all no HOA to deal with.
I could use some assistance with some ideas I have for transimission lines
and overall design of the new QTH.  This will probably be long winded so I
appologize ahead of time.  Also if there is anyone in the DC area, I am in
Sterling, VA by Dulles, who could act as an elmer for me?  Thanks in advance
for any help.

Here is the proposed design in general:

A 9ft Glen Martin rooftop tower with g-5500 rotator.  I have some of the
antennas already, a M2 2MCP22, M2 436CP42UG, and an M2 23CM22EX.  The Dish
for AO-40 is still undecided, but I plan on using a SSB UEK-3000 for the

I plan to run LMR-400 from the antenna's to a tower mounted weatherproof box
(could use some good links for this) to house the pre-amps, ground bus, dc
power bus for the pre-amps.  I expect these runs to be 25' from the antenna
to the pre-amp.  I then need to run about 45' from the tower box to the
outside of the shack.

I want to have 6 coax runs from the inside of the shack to just outside the
shack at the feed point.  the inside runs should be 30' at the maximum.  At
the outside feed point I would like to use N-male to N-female connector to
match up the runs from the tower.  I am propsing this as I don't think I
will ever need more than 6 runs of coax to the inside, and would like a lot
of flexibilty in what I do on the outside.

Here are a few of the questions on the transmission lines:

1. Will I introduce high loss using N-Male to N-Female connections at the
outside feed point of the shack?  Is there a better way to do this so the
inside runs and the outside runs can upgraded, changes, experemented with,
etc. independantly of one another?  Or is this a bad idea all together?

2. Should I consider LMR-600 from the tower box to the outside shack
junction box?  Is LMR-600 overkill? Will I experience problems coupling the
inside runs of LMR-400 to the LMR-600 outside?

3. What are peoples experience with the LMR-400UF?  I am thinking of using
this inside.

Here are some pre-amp questions:

1.  Can I use one DCW-15B (sequence controller, bias-t) from SSB USA to
controll both the SP-2000 and SP-7000 lines of pre-amps from SSB, or do I
need one for each pre-amp?

2. Are these the right pre-amps to be using?

Again Thanks for the Help


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