Ok, I tore apart the recently acquired 1987 300d to do some diagnostic work. Started with a hot compression test yielding 320, 340, 340, 300, 320, 320. Not really bad while not great either. I also decided to pop test the injectors while they were out since I have a friend with a tester. Engine has 250,000 miles on it, with some svo expiramentation from PO in very recent miles. Has a good bit of blowby, so that plus the wvo and lowish compression led me to an MMO soak for the last 2 weeks.

Anyway, I was wondering if any experts could give me input on the injector pop test I just did. 5 injectors gave reasonable spray patterns and were close to spec. Here is an example:
Injector testing - good - YouTube

One was rather stubborn at first and yielded this:
Injector testing - worst one - YouTube

After pumping a bunch of fuel through it it cleaned up, but still streamed a bit. Cleaning did not help. Then I checked some of the others again and noticed with a slow pump I could get a stream at about 75 psi under the actual pop pressure. Is this a bad sign, or just a bad way to test? The bottle jack tester can flow a bunch of fuel, so would be nice to know how to simulate exactly what the IP puts out.