Next thing to do is permanently mate the transmission with the engine. I added a bit of white lithium grease to the hub that inserts into the flexplate. It's a machined tolerance fit so the grease will help with assembly. I also added a bit of anti-sieze to the dowels on the engine's mounting surface. I used the engine lift and leveler to get the engine and trans at exactly the same angle. This ensured that I would be able to push the two all the way together without having to beat on anything. Once they were together, I torqued the transmission housing bolts to GM specs of 37lb/ft.
Next step is to measure the space between the converter mounting surface and the flexplate mounting surface. Circle D recommends using an 1/8" drill bit to check. The gap should be around 1/8" (0.125" +/- 0.025") but no greater than 3/16". When I checked mine, it was greater than 1/8" but less than 3/16" (0.177" actual). In my case, Circle D recommends using an SAE washer to take up some of the space, which they included with my purchase. With these in place, I could barely squeeze in a 7/64 drill bit. So my gap ends up being 0.108" which is close to perfect!
Now, I can bolt the flexplate to the torque converter. I had to remove the starter for this step in order to get to the bolts. I also used the flexplate lock to keep everything in place while I torqued them. I tried to use ARP bolts for this but the bolt heads had zero clearance to the rear engine cover bolts. So, I ended up using the bolts that Circle D supplied with the converter. I torqued these to Circle D specs of 50lb/ft with medium Loctite.
Next was installing the transmission dust cover. I used ARP bolts for this and torqued the bolts to GM specs, 24lb/ft transmission case and 37lb/ft oil pan.
Right about here is where my problems started. I didn't get much further than this only to realize that I have the transmission crossmember in the wrong location. I installed this one back into the original location which is correct for a TH350. Apparently, the 4L80E is a bit longer.
I quickly got the crossmember moved an torqued down so I could try again. Here is the next issue. The top of the engine mount is rubbing the engine stands on both sides. The passenger side is bolted in, but the driver side is off about an inch. I'll stop here for the night. Tomorrow, I will trim the engine mounts and see if things get better.
