Help! Can't get lower unit in the hole

[dbetterred]

'93 mariner 2.0L 135hp

Motor is in neutral

Pulled the lower unit off for winter (sat in basement for cold weather) did water pump, lube and such.
And now I can't get it to slip back in. It slides in until the drive shaft stops all progress. I just can't get it to do anything more. I'm about an inch and a half away from it being in the correct position. I've tried turning the shaft (by hand and with the prop, in gear). When turning the shaft I can't feel anything grinding (like the splines against each other) so I think I am still short of the shaft even starting to slip into it's correct hole. I've tried with the motor tilted up, down and I would try sideways if I could. No luck.

any ideas?