I also use the PPG K-36 primer with k-201 hardener. As for the reducer you will need, it is PPG DT-860 that i use. I think they range from DT 850 to 870 depending on the temperature you will be spraying in.

I usually spray my planes in the basement where it is always 72 Degrees so the DT 860 works just fine for me.

The clear coat that i like is the PPG Concept DCU 2042 along with the DCX 61 Hardener.

For the paint if you want to keep the cost down a little you could also use the OMNI Brand of paint which are the lower end of the PPG line of paints. I have used these with satisfactory results.

But in my own opinion using single stage paints would be much better as it just makes doing any type of repairs to the paint job much easier.