Swapped a 2012 5.3 e38 with 6l80e into a 62 Willy's wagon. Also installed a speartech tap shift shifter from speartech and flashed in a Vette t43 tune. Engine fires right up but when I put in any gear I have no movement at all. Engine just revs up.
At first I had a p0700 and u0100 code (also still have a map voltage low code) but I turned those off. Still no go. ECM and TCM flashed through the obd plug so comm should be fine. Accessory wakeup voltage has 12v.
This is a customer vehicle who just received some bad news and is trying to enjoy what time he has left. I'm trying to get this done asap for him
Any ideas? Thoughts?