'Scuze the minor diversion... 40-ish years ago the Simpson 260 and Triplett Model 60 were the workhorses of the electrical trades. Considering the kit manufacturer tested a properly working sample with a DMM, best bet would be to replicate that setup as closely as possible for a proper comparison to factory spec's.
Could a Simpson 260 do as well? Sure, but there will be more circuit loading and if you know which way to compensate for the meter, no prob. There's the rub... Which direction and how much?
I've used analog meters for years, but the DMM has me so spoiled that going back is like tying one hand to my foot. Auto-Ranging and Fluke's Touch Hold feature are very easy to get used to.
As for accuracy, yeah, even a cheap DMM has the edge.
But... Sitting in front of me as I type this is an original Westinghouse Type PY-5 Portable Volt-Ammeter.http://chem.ch.huji.ac.il/instruments/test/ammeter10.jpg
Mine is similar to the pic, but has three additional terminals in the lower right corner for volts and labeled 150, 300 and 600 respectively. The three terminals along the top edge are labeled +/-, 10 and 5 (amps). Inside the cover is a hand typed certification sheet signed by M Donnelly on September 11, 1939.
Tells me the meter is of the moving vane type and correct to 1/2 of 1% between 15 and 133 cycles AC from 10 to 35 degrees Centigrade. DC accuracy is 1% of full scale. Considering the age... I'd say that's not bad.
Resistance of the 150 volt range is 4,680 ohms, 300 volt range 9,360 ohms. Inductance of the 150 and 300 volt ranges is 360 millihenries. Let's just say this meter would not be my first choice for audio or RF work, but it was definitely "built"... By the Westinghouse Newark Works in Newark, NJ.
Bonus Points: If you had a newspaper from 9/11/1939, what would be the big story near the top of the front page?