I know dad's had not been apart prior to my working on it. He had a very strict policy of replace don't repair after he had issues with having seals done in his 444 circa 84 or so. Very seldom did a saw make it past 2 summers of use with him, and I remember a couple summers that there was another new saw mid season....
Please don't take this the wrong way, not trying to say you're incorrect or don't know what your doing or anything like that... but i have to ask...
Are you familiar with both the 42 op and 242 cp transfer layout?
The 42 transfers have a somewhat unique (for an open port) dished side fed form factor that closely resembles the 242 in that they're basically the same shape,
particularly from the outside.
The difference being that the 42 trans have the typical vertical divider partway down the center, the 242 have the typical horizontal bridge between the uppers and lowers.
If it weren't for the two long rear cylinder bolts the two would be pretty much indistinguishable from the outside without looking into the bore.
I've been involved in past discussions about the difference/definition of open vs. closed port cylinders and there are many who are of the opinion that anything side fed is defined as closed port.
I actually have used the 42/242 and 268/268xp as examples to illustrate that point in this context.
Just noticed you have a 444, I'm jealous, we didn't get many of those south of the border. Lots of 44's though...