1-gauge and gate valve to open or reduce water flow.
2-grease and or gear oil....but in your case grease. Should have one zerk above thrust bearing and possibly one at rear of shaft.
3-Most use wood and fiber glass and some use aluminum for mounts.
4-Most like a smooth non cluttered hull and/or the weight that stuff brings. But if your going to use for fun and want the ease..you can ad these things with pop up features to retain the smooth look. Suction cup style lights for example...

Its usually right out of the pump before T. In your case sounds about right for headers. You can ad a gate valve/valves to regulate the amout of water going to both headers and the block. Some will install a gate up near driver seat to shut the water off to headers for a quick pass or for ease of adjustment.  Sometimes to much water to your headers could lead to water in the block.   

In the fitting that comes out of the pump, the hole is a little smaller. It is brass and appears to be made that way. All the hoses are 5/8 ID but the fitting looks like it is 3/8- 7/16.

Ok, the Kachina is finally done and on the water. It has been a year in the making and I have learned so much in the rebuild of this boat that is totally different from my other outboard speed rigs.

1- Donnie Drier Race Engines of Lansing New York rebuilt my 472ci alum. head BBF, it is running like a a wet dream and making just over   500hp. Dyno-Port in Fleming, New York ceramic coated my Bassett headers after I installed reverse cones in them.

2- John at Bardeens  Upholstery in Penn Yan, New York did a great job stitching together the new vinyl and foam for the seats and Neil Purdy of Purdybuilt Fabrication in Moravia, New York did my seat frames and some other fab work around the engine compartment to make it all look neat.

3- Kudos out to Chris Leanord of C&M Transportation in Moravia, New York for the the use of his shop and excavator for removing and reinstalling the engine and Dave Marcellus of Finger Lakes Fabrication for making a killer thermostat housing that fit a thermostat and around my DUI HEI distributor. Very nice!!!

This is my first pump boat, and I must admit that I am totally hooked on the insane amount of acceleration and the ease of maintenance with a pump. I will put some pics up very soon, as I need my teenage daughter to walk me through this process.  And here is to praying for flat water on the Finger Lakes until it is too cold to boat here. Cheers!!!