I too am planning a TKX swap for my 66 El Camino. I have a Muncie four speed now, my problem is I want the 18083 trans and have been waiting since December for it to be available. Last communication I had is possibly May delivery. I am running a SBC with 3.31 gearing and 26 inch tire. I feel the 3.27 first gear and .72 OD would be best in my application. I have also ordered the trans mount, crossmember, reverse pigtail, Dakota gauge pigtail and offset shifter. Maybe we get lucky and post the installs together.