Tach went erratic and now stopped working after manual tranny swap
 

Could this be coincidental? It had no issues on test drives with auto. Then 1st 2 test drives with manual was ok. Of course on the way home she acted up, but I was driving in a downpour (not that it should matter). Next day all good. Then she got erratic again and quit all together.
Note. The drive before erratic followed by ultimate failure..... I turn the key position on and the tach started to dance a bit then went normal.
any ideas of what to check? Could this just be the typical fd tach issue and just a coincidence?
Please help... what fun is a rotary without a tach?? These electric issues are my biggest weakness

K..... the tach is back on today..... wtf

would still like to have an idea of what to look for. What fun is the 7 without a tach??