Mark, it works out pretty good. They make the guides, intake valve seats, valves, titanium keepers, and sell the custom springs. Also, they sell the cam follower buckets with the shims between the valve tips and the bottoms of the buckets. I sent them the cylinder head, cams, a manifold, carb, exhaust pipe stub, and an air filter. Also, lots of money. The head comes back ready to be bolted on with flow test results.
The head manifold, and carbs are at Kibblewhite. Fortunately there are enough parts in the junk pile to bolt up a simulation of the race motor. The carbs are parallel to each other and close together. There is this big square frame tube near them and it prevents the installation of large filters. Some adapters are needed so the filters can be located where there is room for them. Also, there needs to be enough space left over for the battery, starter solenoid, fuse box, blinker relay, and some other relay that I do not know what it is for.
A few hours were spent with the K and N on-line catalog. A pair of RV1090 cylindrical filters, 3.5 inches wide and 6 inches long, with 2.25 inch spigots cocked at a 10 degree angle will fit in the gaps between the things that I cannot move. I ordered a pair with the socks that go over them to keep the salt away from the elements. The plan is to position them on the bike in the only places they logically fit and then to figure out how to connect them to the carbs and where to put all of the other carp that belongs on that part of the bike.
The "Horsepower Chain" book gives some good info on single runner intake systems. A plenum helps to dampen out the intake pulses. This lessens the intensity of the big gulp through the filter when the intake valve opens. This reduces deltaP factor and promotes volumetric efficiency. The plan is to build plenums into the connections between the filters and the carbs and to connect the plenums to each other. This project will keep the ol' walrus busy and out of trouble for a week or two.