Good Deal on the Instruction Manuel!! (I'm pretty sure it should look very similar to the 45's manual...Kinda Curious to know...The 45's an spin off of the 60 so I'm just guessing the manuals will be very similar??)

You didn't specifically state...I didn't specifically ask...But just to confirm:
You have the Check Valve installed and oriented per the .45's Diagram...Correct??

What do you have for an Exhaust System??

Confirm the Regulator Adjustment screw is set Flush with the housing...

If it were me:
I'd get on the horn to YS Parts and Service and order a couple of Diaphram/Gasket/Spring/Plunger set-Ups(Same as .45's so they will be available)...I'd also order an O-Ring and Gasket set if available...(60 parts are apparently tough to come by...I "Think" that means Hard parts?? I'd assume gaskets/O-Rings ect should be out there??)

I'd get a couple of Fuel Filters and Check Valves too...

Closely Inspect the needle valve...I may just get one "just to have"...At least a set of Needle valve O-Rings(If Applicable...The 45 Has them...Assuming the 60 does too)

Inspect the carb for Dirt, Corrosion ect...

Replace the Diaphram,Spring,Plunger,Gasket...Check that assemby for dirt ect...(Note the possible gasket interference upon re-assembly...)

Replace the Check Valve and Fuel Filter...

Use Medium size Fuel Tubing for the Fuel System...

Confirm the Fuel System is Air Tight...

Fresh Fuel...

If you elect to use After Run Oil...Only use Ultra Oil...

Just My Opinions...

Good Luck getting her going!!

Chuck