Tascam Portastudio 464 transport buttons work perfectly in clean mode only

[SueDonim]

Hello everyone. I'm brand new here, searching for a solution. Apologies if I have not posted in the right spot. I have a Tascam 464 that I purchased new about 35 years ago now. Like many it sat unused for quite some time. I know it was working up until about 10 years ago. Anyways I pulled it out to play a tape and it was no longer working. I replaced the C-gear, the capstan belt, and cleaned and lubed everything. I was able to figure out how to get into "clean mode" by messing around with the buttons. I had hoped there was some sort of "factory reset". In clean mode: all functions now worked. When I got out of clean mode none of the buttons worked. I sat there dumbfounded and figured it had to be a logic issue. I turned it on while holding pause+record and viola, that allowed to buttons to work normally again. I let an entire tape run from beginning to end twice. I came back to it later and it was doing the play for a couple of seconds then stop thing. So I went BACK in, cleaned it better, lubed everything that I could see was moving, and then reassembled. Same thing. In clean mode all the buttons work, but in normal mode nothing works. AND my pause+record trick no longer worked to get things operating normally. I am officially at a loss for what to do next. Would appreciate any insight to possible solutions. Thanks in advance.