The "X" suffix (root number for your 8100) designates a preset gap of 1.1mm, so you'd have to adjust them and you have to be uber-careful about it since it's easy to damage the fine-wire center electrode. The ground electrode has a raised design and is blunt-cut, Nickel-Yttrium and Platinum.

The ground electrode on the 7422 is a traditional design with a taper cut; how much difference that makes is anyone's guess.

The Bosch 9652, which is a fine wire iridium plug, has been used by many folks without any issues. The ground electrode on it apes the 7422.

I know lots of people who have used the 7422 and the 9652 plugs, but I don't know anyone who has used the 8100 in the M112 or M113 engines. You might search around on some of the other forums for some feedback if you are leaning that way.

I was going to attach the Bosch guide which has lots of useful information, but PP only allows a 732kb pdf file size (apparently they think it is 2002), so I'll just give you the link to it:
http://mdm.boschwebservices.com/vpf-media/SparkPlugs/PDF/Catalog_Spark_Plugs.pdf

Hope that helps.

Good luck.