That's certainly one way!! I could also pull the rear cover and I think there is a stamping inside that should indicate if it's a 4.11. I am pretty sure the diff has been changed, or minimally cleaned, it looks rather new. The 5-speed is a Motorsport Auto unit. Don't know if they still sell them, but it's not a T-5 from a Mustang or ZX. I am curious if MSA just rebadged or mimicked what was in a T-5, but I am not up to speed on what the gearing was in them. Here's what is interesting. When I am below 3000 RPMs, the motor coughs and such, but once you get past 3000, the thing takes off. I figured that was due to the cam, I bet the previous previous owner dumped something in there without doing the port/valves/exhaust, etc. It doesn't burble at idle, so it can't be too hot of a cam, but it's sluggish at low revs. I also noticed it ticks a bit. I know the Z's are known for this, but it seems pretty loud. I have good oil pressure, and it's not smoking, so maybe there's just a need to get that head off and have it done. It will take me some time. I have to start tinkering with the E-type too -- while quite similar to the Z, it's different enough to scare me more.