Why you gotta be hating on my LT1s? Lol
Not so much having, just doesn't mesh with this car supposedly being a budget build.
It extends the build time, adds lots to the cost, and, injects the need for parts which aren't so widely available and are trending towards costliness.
Plus I ain't afraid of no wires, the computer controlledness of the 4L60E doesn't bother me, I actually prefer it.
There's many hundreds of dollars in extra costs to use the electronically controlled transmission. 4l60s were a poor decision that gm should've bypassed entirely. I like the keep it simple principle where it works. On a conversion I have a hard time seeing the reason for the added expense and effort where power levels aren't going to be high, and again, if it ever headed there I'd skip over the 60 series trans anyways. Again, on a supposed budget build... I dunno, just see it different.
What's more, it's from a fbody.... it's probably been flogged to hell. My guess is it came from one of two things:
A - an abused and wrecked higher mileage car, or,
B - someone was tired of optispark issues and had some trans slippage, decided to put a better driveline setup in.
A leakdown test seems like a great idea. Hopefully the autozone has the tool.
Another idea is get the vin numbers off the case/block, and run a history report. It could at least tell you the true mileage.