[DirtyLarry]

Funny, my 8.1L tosses a code for a MAF every now and then again as well. I don’t recall if it was a high or low voltage code though but it does it a couple times a year. It always runs great even with the light comes on so that has me thinking I over oiled my K&N filter. You might want to check that if you used a K&N. Also make sure you have the MAF going the right way, as they are easy to install backasswards with the airflow going the wrong way.

That is a bummer about the dash electrical. Is the gauge pegged at 3 o’clock? If so, I believe that is a ground issue, which may be upstream instead of at the frame.

Not sure what to say on the other stuff but knowing you have the temp gauge set up exactly how it was on the old 454 leads one to think there is sometangwong with the wiring between the sending unit and temp gauge in the cluster. Probably where ever that issue is found will fix the other stuff too.

Working out the bugs is the funnest part, well….so they say. Working out the bugs on mine was actually quite frustrating!