Tim,
I am going through the same thing on the 59-261 I am putting in a 51-3100. The original installation on the manifold won't work in the 1/2 ton due to the spatial constraints of the large filter and the steering box. There is enough space on the firewall directly above the steering column to mount the filter housing with clearance to remove the canister when changing the filter.
The original lines that came with the engine had a fitting with the 1/2 NPT as mentioned on one end with a female flare fitting that the metal part of the line screwed into. One of these special fittings had a 1/8 NPT tap in the side for the oil pressure line. The metal line was joined to a flexible pressure hose by means of a special soldered fitting crimped onto the hydraulic hose. The filter end of the hose has a fitting that is crimped onto the flex hose and then has another flare fitting which mounts onto the flared elbows mounted within the aluminum housing.
I have a fenton dual manifold installed and there is enough clearance for the oil lines but since they are running very close to the exhaust, they need to be metal up past the point where heat generated by the exhaust pipes will not do any damage to the flex hose.
I took pics of how I wanted the lines bent to a shop who specializes in all sorts of hydraulic fittings and lines. I can e-mail them if you want to see how I am setting it up. There are slightly different fittings available now that may improve the looks of your new set-up. Use of SS lines from the engine enable you to polish them up before installation, and the externally braided lines for the flex part are also SS. This would be nice to complement the braided rad/heater hose kits that are available.
Another note about the filter canister- it should hold a AC PF 141 filter. This may be an added benefit if you want to spruce up the engine compartment even further. This is the same filter set up used on many SB chevys before the spin-on filters were introduced and you can find chrome ones at swap meets cheap if you look or possibly from JEGS and others.
