I was thinking about purchasing aluminum heads for my 37' Zephyr. Could someone tell me what I should expect to spend for a decent pair? Also, what should I look for to make sure they are correct for a 37'?

A decent pair will probably run you around $500 and up. One reason is that so few have survived. Whatever good qualities they had (heat dissipation and weight) was counterbalanced by the fact that they were very susceptible to corrosion. Also, it seems to me there are more susceptible to head gasket leaks since they can only be tightened to about 40 ft. lbs. But they do look great!

The '36 and '37 heads have no markings at all on the top surface, and no boss for the water heater outlet or a temperature sensing unit. There are aftermarket heads out there that look similar. True factory heads will have "HT Lincoln H6050" or "6049" on the bottom edges.

Wow, thank you very much for your info. It was more then I could have asked for!

By the way, your 37' is looking beautiful! better then the day it rolled off the showroom floor I would imagine. I can't wait to see it finished!