More experience....
Andy, that's a great collection of comments and advice.
The piston-seal experience suggests to me that running on glow enough to verify that the piston isn't squeaking to a halt at the top, and then going to the Diesel conversion, might be a valid choice. Especially since the operating temperatures of glow and Diesel (I think) vary so much from one to the other.
1I don't have the luxury of a pile of pistons and liners to mix and match, and I don't see that I want to. That alone makes the conversion to make a useless engine do some valid work seriously uneconomic. Run-what-ya-brung is fine, but there's limits.
And you're sure right about an experienced eye hanging around. That's how I got the little Diesel experience I have.