I am running the Paragon Products 1 5/8 headers. And I am just struggling how to route the clutch and speedometer cables without burning them up. I have tried several heat wraps and tried tucking them up everywhere I can think and still I get melting when the engine is hot.

Anyone solved this?

See if you can find a race shop or use mail order and buy what's called "fire sleeving" and get enough to build up at least two layers, perferably three total, one inside the other. Then get some soft aluminum sheet about 8 to 10 inches wide and several feet long. Use a sheet metal brake and bend the aluminum into an shape like /\/\/\/\/\/\ and fasten it between the headers and the fire sleeve with some clamps. I found that teflon lined cables tended to melt no matter what I did but non-lined cables worked just fine. One thing to make sure of is to always do a cool down lap so the headers will cool down several hundred degrees before you stop at the pits.