So this is interesting. I posted sort of a similar post yesterday about fuel quantity and fuel pressure, but I can answer this for you...sort of. TBH I read your post yesterday, but not carefully enough. Sorry about that.
I purchased and installed my EDM 350 in 2018. At that time I installed CHT and EGT (of course) but I also installed oil temp and oil pressure. I purchased both the temp and pressure senders from JPI (and I probably paid $270
). The pressure sender was, I am sure, a 2 wire and I am also pretty sure it was VDO. The sender terminals were screw type and I recall simply crimping ring terminals. Naturally I took a number of pics of the entire installation and, also naturally, I did not take a picture of the pressure sender.
I am running out today to do some work on the EDM and quite conveniently, the top cowl is off. So later today I will follow up this post with a pic and as much information as I can gather for you.
It would be interesting to know why JPI decided that the old VDO oil pressure sender isn't good enough any more. In 3 years and 200 hours, it's worked spectacularly well in the -4.