Gary,
Just for your info, — Anything about most Heathkit stuff should be on one of these 2 sites.
https://www.vintage-radio.info/heathkit or http://tubularelectronics.com/Heath_Manual_Collection/
The schematic of the IG-72 is there, but little else. It is an audio generator only not an RF signal generator.
By the way, I think as a starting point , one of the voltmeters from Canadian Tire might be worth looking at.
I have purchased the stock number #052-0052-2 on sale and found it very reliable.
It does frequency and can measure capacitors.
Flukes are very nice meters and I have one but the CTC one does a lot of what I need at a lot less money.
TTFN
John G