Upgrading LT-8s to 3-bar MAP
 

I'm hoping to run 25+ this summer, so I will need to upgrade to a GM 3-bar. There is a wiring schematic for it in the manual, but I've noticed a few posts saying they must be upgraded internally too.

Is there anyone in the US that does this? How much would it cost and what would be the turnaround time? Would I still be able to use the map I had tuned before?

find any info?

Nope