It was the earliest board set.
I think there was a another board style introduced before 2.0 which was more stable though. I think your game might have these.
Yes it sounds like Jordan's is the 7.5v version, almost a 'version 1.5 LED' type thing. There are a lot of 7.5v board owners that were rock solid after their upgrade and of course it might have been the 75th Ruby Red LE that starting first shipping with the 7.5v and eventually JJP starting installing the version 2.0 LED in all remaining production WOZ runs. They also released a 2.0 LED upgrade kit which ran me about $1250 CDN. Unfortunate but worth every penny in my opinion. All future JJP pins had this newly designed LED system. I would buy a WOZ only if it had a 7.5v system at minimum or of course with a 2.0 LED kit installed. [Hope this helps someone looking]
On my ECLE I had the original untouched 5.0v (version 1.0 LED) and I had problems as mentioned.
JJP then they came out with a 5.0v 'buffered/filtered' (we'll call this version1.25 LED) which was a modification which had a small PCB littered with SMD. I believe that it was supposed to address the issue(s) with static electricity potentially killing the original boards. I did a full forklift from my 5.0 and the problems came back. I then went to the 2.0 upgrade kit at my cost, see below.
They also came out with a 7.5v boardset which may have also required a power supply replacement or similar. Now don't quote me on the timing of version release though. I do think that JJP were ok with a 5.0 version owner dropping in a one or two 7.5v boards but any more than that, they advised moving to a full 7.5v swap.
The final 2.0 LED version kit is a complete redesign right down to the small satellite single LED PCBs. The kit requires replacement of all LED PCBs, the wiring harnesses and power supply. This is actual a very good thing as it eliminates the in-line 'serial' wiring as well. It's great that this is an option for those who decide it is necessary but most of those were the 5.0v original and buffered/filtered users.
This said, I still have a full functioning 5.0 buffered/filtered boardset with powersupply and all wiring as well as almost a second set of boards, some functional some not. Just for fun, here is what those look like: (you can see the mini buffer/filter PCB on all of the small numbers boards and some of the large have them and some don't. JJP really worked at trying to resolve the issues back in the day.
https://photos.app.goo.gl/VewgeTd363dFbuan7